Hepatitis C virus inhibitors

ABSTRACT

The present disclosure relates to compounds, compositions and methods for the treatment of hepatitis C virus (HCV) infection. Also disclosed are pharmaceutical compositions containing such compounds and methods for using these compounds in the treatment of HCV infection.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser.No. 61/028,011 filed Feb. 12, 2008.

The present disclosure is generally directed to antiviral compounds, andmore specifically directed to compounds which can inhibit the functionof the NS5A protein encoded by Hepatitis C virus (HCV), compositionscomprising such compounds, and methods for inhibiting the function ofthe NS5A protein.

HCV is a major human pathogen, infecting an estimated 170 millionpersons worldwide—roughly five times the number infected by humanimmunodeficiency virus type 1. A substantial fraction of these HCVinfected individuals develop serious progressive liver disease,including cirrhosis and hepatocellular carcinoma.

Presently, the most effective HCV therapy employs a combination ofalpha-interferon and ribavirin, leading to sustained efficacy in 40% ofpatients. Recent clinical results demonstrate that pegylatedalpha-interferon is superior to unmodified alpha-interferon asmonotherapy. However, even with experimental therapeutic regimensinvolving combinations of pegylated alpha-interferon and ribavirin, asubstantial fraction of patients do not have a sustained reduction inviral load. Thus, there is a clear and long-felt need to developeffective therapeutics for treatment of HCV infection.

HCV is a positive-stranded RNA virus. Based on a comparison of thededuced amino acid sequence and the extensive similarity in the 5′untranslated region, HCV has been classified as a separate genus in theFlaviviridae family. All members of the Flaviviridae family haveenveloped virions that contain a positive stranded RNA genome encodingall known virus-specific proteins via translation of a single,uninterrupted, open reading frame.

Considerable heterogeneity is found within the nucleotide and encodedamino acid sequence throughout the HCV genome. At least six majorgenotypes have been characterized, and more than 50 subtypes have beendescribed. The major genotypes of HCV differ in their distributionworldwide, and the clinical significance of the genetic heterogeneity ofHCV remains elusive despite numerous studies of the possible effect ofgenotypes on pathogenesis and therapy.

The single strand HCV RNA genome is approximately 9500 nucleotides inlength and has a single open reading frame (ORF) encoding a single largepolyprotein of about 3000 amino acids. In infected cells, thispolyprotein is cleaved at multiple sites by cellular and viral proteasesto produce the structural and non-structural (NS) proteins. In the caseof HCV, the generation of mature non-structural proteins (NS2, NS3,NS4A, NS4B, NS5A, and NS5B) is effected by two viral proteases. Thefirst one is believed to be a metalloprotease and cleaves at the NS2-NS3junction; the second one is a serine protease contained within theN-terminal region of NS3 (also referred to herein as NS3 protease) andmediates all the subsequent cleavages downstream of NS3, both in cis, atthe NS3-NS4A cleavage site, and in trans, for the remaining NS4A-NS4B,NS4B-NS5A, NS5A-NS5B sites. The NS4A protein appears to serve multiplefunctions, acting as a cofactor for the NS3 protease and possiblyassisting in the membrane localization of NS3 and other viral replicasecomponents. The complex formation of the NS3 protein with NS4A seemsnecessary to the processing events, enhancing the proteolytic efficiencyat all of the sites. The NS3 protein also exhibits nucleosidetriphosphatase and RNA helicase activities. NS5B (also referred toherein as HCV polymerase) is a RNA-dependent RNA polymerase that isinvolved in the replication of HCV.

Compounds useful for treating HCV-infected patients are desired whichselectively inhibit HCV viral replication. In particular, compoundswhich are effective to inhibit the function of the NS5A protein aredesired. The HCV NS5A protein is described, for example, in Tan, S.-L.,Katzel, M. G. Virology 2001, 284, 1-12; and in Park, K.-J.; Choi, S.-H,J. Biological Chemistry 2003.

In a first aspect the present disclosure provides a compound of Formula(I)

or a pharmaceutically acceptable salt thereof, wherein

a, b, and d are each selected from CH and N; provided at least one of a,b, and d is N;

n is 1, 2, 3, 4, or 5;

u is 0, 1, 2, or 3;

A is selected from phenyl and a six-membered heteroaromatic ringcontaining one, two, or three nitrogen atoms;

B is a five-membered aromatic ring containing one, two, or threeheteroatoms independently selected from nitrogen, oxygen, and sulfur;

R¹ is selected from hydrogen, alkyl, and haloalkyl;

R² is selected from hydrogen, alkoxy, alkyl, haloalkoxy, haloalkyl,heterocyclyl, and —NR^(c)R^(d);

each R³ is independently selected from alkoxy, alkoxyalkyl,alkoxycarbonyl, alkyl, arylalkoxycarbonyl, carboxy, formyl, halo,haloalkyl, hydroxy, hydroxyalkyl, —NR^(a)R^(b), (NR^(a)R^(b))alkyl, and(NR^(a))carbonyl;

R⁴ is selected from hydrogen, alkoxyalkyl, alkoxycarbonyl,alkoxycarbonylalkyl, alkyl, arylalkoxycarbonyl, carboxy, haloalkyl,heterocyclylalkyl, hydroxyalkyl, (NR^(a)R^(b))carbonyl, andtrialkylsilylalkoxyalkyl;

R⁵ is selected from

m is 0, 1, or 2;

o is 1, 2, or 3;

s is independently 0, 1, 2, 3, or 4;

X is independently selected from O, S, S(O), SO₂, CH₂, CHR⁶, and C(R⁶)₂;provided that when n is 0, X is selected from CH₂, CHR⁶, and C(R⁶)₂;

each R⁶ is independently selected from alkoxy, alkyl, aryl, halo,haloalkyl, hydroxy, and —NR^(a)R^(b), wherein the alkyl can optionallyform a fused three- to six-membered ring with an adjacent carbon atom,wherein the three- to six-membered ring is optionally substituted withone or two alkyl groups;

each R⁷ is independently selected from hydrogen and R¹¹—C(O)—, andR¹¹—C(S)—;

R⁸ is selected from hydrogen and alkyl;

R⁹ and R¹⁰ are each independently selected from hydrogen, alkenyl,alkoxyalkyl, alkyl haloalkyl, and (NR^(a)R^(b))alkyl; or,

R⁹ and R¹⁰, together with the carbon atom to which they are attached,form a five or six membered saturated ring optionally containing one ortwo heteroatoms selected from NR^(z), O, and S; wherein R^(z) isselected from hydrogen and alkyl; and

each R¹¹ is independently selected from alkoxy, alkoxyalkyl,alkoxycarbonyl, alkoxycarbonylalkyl, alkyl, alkylcarbonylalkyl, aryl,arylalkenyl, arylalkoxy, arylalkyl, aryloxyalkyl, cycloalkyl,(cycloalkyl)alkenyl, (cycloalkyl)alkyl, cycloalkyloxyalkyl, haloalkyl,heterocyclyl, heterocyclylalkenyl, heterocyclylalkoxy,heterocyclylalkyl, heterocyclyloxyalkyl, hydroxyalkyl, —NR^(c)R^(d),(NR^(c)R^(d))alkenyl, (NR^(c)R^(d))alkyl and (NR^(c)R^(d))carbonyl.

In a first embodiment of the first aspect, the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein R⁵ is

In a second embodiment of the first aspect wherein m is 1.

In a third embodiment of the first aspect, the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof; wherein R⁵ is

wherein X is CH₂.

In a fourth embodiment of the first aspect, the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein R⁵ is

wherein s is 0.

In a fifth embodiment of the first aspect, the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein R⁵ is

wherein R⁷ is selected from hydrogen and R¹¹—C(O)—. In a sixthembodiment R¹¹ is independently selected from arylalkyl,(cycloalkyl)alkyl, and (NR^(c)R^(d))alkyl.

In a seventh embodiment of the first aspect the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein u is 0.

In an eighth embodiment of the first aspect the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein R⁴ is hydrogen.

In a ninth embodiment of the first aspect the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein wherein R¹ is hydrogen.

In a tenth embodiment of the first aspect the present disclosureprovides a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, wherein n is 2; and one R² is hydrogen and the other isselected from heterocyclyl and —NR^(c)R^(d).

In a second aspect the present disclosure provides a compound of Formula(II)

or a pharmaceutically acceptable salt thereof, wherein

R⁷ is selected from hydrogen and R¹¹—C(O)—; and

R¹¹ is independently selected from alkoxy; alkoxyalkyl, alkoxycarbonyl,alkoxycarbonylalkyl, alkyl, alkylcarbonylalkyl, aryl, arylalkenyl,arylalkoxy, arylalkyl, aryloxyalkyl, cycloalkyl, (cycloalkyl)alkenyl,(cycloalkyl)alkyl, cycloalkyloxyalkyl, haloalkyl, heterocyclyl,heterocyclylalkenyl, heterocyclylalkoxy, heterocyclylalkyl,heterocyclyloxyalkyl, hydroxyalkyl, —NR^(c)R^(d), (NR^(c)R^(d))alkenyl,(NR^(c)R^(d))alkyl, and (NR^(c)R^(d))carbonyl.

In a first embodiment of the second aspect R¹¹ is selected from alkoxy,alkyl, arylalkyl, and (NR^(c)R^(d))alkyl.

In a third aspect the present disclosure provides a compound selectedfrom:

or a pharmaceutically acceptable salt thereof.

In a fourth aspect the present disclosure provides a compositioncomprising a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, and a pharmaceutically acceptable carrier. In a firstembodiment of the fourth aspect the composition further comprises one ortwo additional compounds having anti-HCV activity. In a secondembodiment of the fourth aspect at least one of the additional compoundsis an interferon or a ribavirin. In a third embodiment of the fourthaspect the interferon is selected from interferon alpha 2B, pegylatedinterferon alpha, consensus interferon, interferon alpha 2A, andlymphoblastiod interferon tau.

In a fourth embodiment of the fourth aspect the present disclosureprovides a composition comprising a compound of Formula (I), or apharmaceutically acceptable salt thereof a pharmaceutically acceptablecarrier, and one or two additional compounds having anti-HCV activity,wherein at least one of the additional compounds is selected frominterleukin 2, interleukin 6, interleukin 12, a compound that enhancesthe development of a type 1 helper T cell response, interfering RNA,anti-sense RNA, Imiqimod, ribavirin, an inosine 5′-monophospatedehydrogenase inhibitor, amantadine, and rimantadine.

In a fifth embodiment of the fourth aspect the present disclosureprovides a composition comprising a compound of Formula (I), or apharmaceutically acceptable salt thereof, a pharmaceutically acceptablecarrier, and one or two additional compounds having anti-HCV activity,wherein at least one of the additional compounds is effective to inhibitthe function of a target selected from HCV metalloprotease, HCV serineprotease, HCV polymerase, HCV helicase, HCV NS4B protein, HCV entry, HCVassembly, HCV egress, HCV NS5A protein, and IMPDH for the treatment ofan HCV infection.

In a fifth aspect the present disclosure provides a method of treatingan HCV infection in a patient, comprising administering to the patient atherapeutically effective amount of a compound of Formula (I), or apharmaceutically acceptable salt thereof. In a first embodiment of thefifth aspect the method further comprises administering one or twoadditional compounds having anti-HCV activity prior to, after orsimultaneously with the compound of Formula (I), or the pharmaceuticallyacceptable salt thereof. In a second embodiment of the fifth aspect atleast one of the additional compounds is an interferon or a ribavirin.In a third embodiment of the fifth aspect the interferon is selectedfrom interferon alpha 2B, pegylated interferon alpha, consensusinterferon, interferon alpha 2A, and lymphoblastiod interferon tau.IMPDH for the treatment of an HCV infection.

In a fourth embodiment of the fifth aspect the present disclosureprovides a method of treating an HCV infection in a patient, comprisingadministering to the patient a therapeutically effective amount of acompound of Formula (I) or a pharmaceutically acceptable salt thereofand one or two additional compounds having anti-HCV activity prior to,after or simultaneously with the compound of Formula (I), or thepharmaceutically acceptable salt thereof, wherein at least one of theadditional compounds is selected from interleukin 2, interleukin 6,interleukin 12, a compound that enhances the development of a type 1helper T cell response, interfering RNA, anti-sense RNA, Imiqimod,ribavirin, an inosine 5′-monophospate dehydrogenase inhibitor,amantadine, and rimantadine.

In a fifth embodiment of the fifth aspect the present disclosureprovides a method of treating an HCV infection in a patient, comprisingadministering to the patient a therapeutically effective amount of acompound of Formula (I), or a pharmaceutically acceptable salt thereofand one or two additional compounds having anti-HCV activity prior to,after or simultaneously with the compound of Formula (I), or thepharmaceutically acceptable salt thereof, wherein at least one of theadditional compounds is effective to inhibit the function of a targetselected from HCV metalloprotease, HCV serine protease, HCV polymerase,HCV helicase, HCV NS4B protein, HCV entry, HCV assembly, HCV egress, HCVNS5A protein, and IMPDH for the treatment of an HCV infection.

Other embodiments of the present disclosure may comprise suitablecombinations of two or more of embodiments and/or aspects disclosedherein.

Yet other embodiments and aspects of the disclosure will be apparentaccording to the description provided below.

The compounds of the present disclosure also exist as tautomers;therefore the present disclosure also encompasses all tautomeric forms.

The description of the present disclosure herein should be construed incongruity with the laws and principals of chemical bonding. In someinstances it may be necessary to remove a hydrogen atom in orderaccommodate a substitutent at any given location.

It should be understood that the compounds encompassed by the presentdisclosure are those that are suitably stable for use as pharmaceuticalagent.

It is intended that the definition of any substituent or variable (e.g.,R², R³ and R⁶) at a particular location in a molecule be independent ofits definitions elsewhere in that molecule. For example, when s is 2,each of the two R⁶ groups may be the same or different.

All patents, patent applications, and literature references cited in thespecification are herein incorporated by reference in their entirety. Inthe case of inconsistencies, the present disclosure, includingdefinitions, will prevail.

As used in the present specification, the following terms have themeanings indicated:

As used herein, the singular forms “a”, “an”, and “the” include pluralreference unless the context clearly dictates otherwise.

Unless stated otherwise, all aryl, cycloalkyl, and heterocyclyl groupsof the present disclosure may be substituted as described in each oftheir respective definitions. For example, the aryl part of an arylalkylgroup may be substituted as described in the definition of the term‘aryl’.

The term “alkenyl,” as used herein, refers to a straight or branchedchain group of two to six carbon atoms containing at least onecarbon-carbon double bond.

The term “alkenyloxy,” as used herein, refers to an alkenyl groupattached to the parent molecular moiety through an oxygen atom.

The term “alkenyloxycarbonyl,” as used herein, refers to an alkenyloxygroup attached to the parent molecular moiety through a carbonyl group.

The term “alkoxy,” as used herein, refers to an alkyl group attached tothe parent molecular moiety through an oxygen atom.

The term “alkoxyalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three alkoxy groups.

The term “alkoxyalkylcarbonyl,” as used herein, refers to an alkoxyalkylgroup attached to the parent molecular moiety through a carbonyl group.

The term “alkoxycarbonyl,” as used herein, refers to an alkoxy groupattached to the parent molecular moiety through a carbonyl group.

The term “alkoxycarbonylalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three alkoxycarbonyl groups.

The term “alkyl,” as used herein, refers to a group derived from astraight or branched chain saturated hydrocarbon containing from one tosix carbon atoms. In the compounds of the present disclosure, when m is1 or 2; X is CHR⁶, and R⁶ is alkyl, each alkyl can optionally form afused three- to six-membered ring with an adjacent carbon atom toprovide one of the structures shown below:

where z is 1, 2, 3, or 4, w is 0, 1, or 2, and R⁵⁰ is alkyl. When w is2, the two R⁵⁰ alkyl groups may be the same or different.

The term “alkylcarbonyl,” as used herein, refers to an alkyl groupattached to the parent molecular moiety through a carbonyl group.

The term “allylcarbonylalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three alkylcarbonyl groups.

The term “alkylcarbonyloxy,” as used herein, refers to an alkylcarbonylgroup attached to the parent molecular moiety through an oxygen atom.

The term “alkylsulfanyl,” as used herein, refers to an alkyl groupattached to the parent molecular moiety through a sulfur atom.

The term “alkylsulfonyl,” as used herein, refers to an alkyl groupattached to the parent molecular moiety through a sulfonyl group.

The term “aryl,” as used herein, refers to a phenyl group, or a bicyclicfused ring system wherein one or both of the rings is a phenyl group.Bicyclic fused ring systems consist of a phenyl group fused to a four-to six-membered aromatic or non-aromatic carbocyclic ring. The arylgroups of the present disclosure can be attached to the parent molecularmoiety through any substitutable carbon atom in the group.Representative examples of aryl groups include, but are not limited to,indanyl, indenyl, naphthyl, phenyl, and tetrahydronaphthyl. The arylgroups of the present disclosure are optionally substituted with one,two, three, four, or five substituents independently selected fromalkoxy, alkoxyalkyl, alkoxycarbonyl, alkyl, alkylcarbonyl, a second arylgroup, arylalkoxy, arylalkyl, arylcarbonyl, cyano, halo, haloalkoxy,haloalkyl, heterocyclyl, heterocyclylalkyl, heterocyclylcarbonyl,hydroxy, hydroxyalkyl, nitro, —NR^(x)R^(y), (NR^(x)R^(y))alkyl, oxo, and—P(O)OR₂, wherein each R is independently selected from hydrogen andalkyl; and wherein the alkyl part of the arylalkyl and theheterocyclylalkyl are unsubstituted and wherein the second aryl group,the aryl part of the arylalkyl, the aryl part of the arylcarbonyl, theheterocyclyl, and the heterocyclyl part of the heterocyclylalkyl and theheterocyclylcarbonyl are further optionally substituted with one, two,or three substituents independently selected from alkoxy, alkyl, cyano,halo, haloalkoxy, haloalkyl, and nitro.

The term “arylalkenyl,” as used herein, refers to an alkenyl groupsubstituted with one, two, or three aryl groups.

The term “arylalkoxy,” as used herein, refers to an aryl group attachedto the parent molecular moiety through an alkoxy group.

The term “arylalkoxyalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three arylalkoxy groups.

The term “arylalkoxyalkylcarbonyl,” as used herein, refers to anarylalkoxyalkyl group attached to the parent molecular moiety through acarbonyl group.

The term “arylalkoxycarbonyl,” as used herein, refers to an arylalkoxygroup attached to the parent molecular moiety through a carbonyl group.

The term “arylalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three aryl groups. The alkyl part of thearylalkyl is further optionally substituted with one or two additionalgroups independently selected from alkoxy, alkylcarbonyloxy, halo,haloalkoxy, haloalkyl, heterocyclyl, hydroxy, and —NR^(c)R^(d), whereinthe heterocyclyl is further optionally substituted with one or twosubstituents independently selected from alkoxy, alkyl, unsubstitutedaryl, unsubstituted arylalkoxy, unsubstituted arylalkoxycarbonyl, halo,haloalkoxy, haloalkyl, hydroxy, and —NR^(x)R^(y).

The term “arylalkylcarbonyl,” as used herein, refers to an arylalkylgroup attached to the parent molecular moiety through a carbonyl group.

The term “arylcarbonyl,” as used herein, refers to an aryl groupattached to the parent molecular moiety through a carbonyl group.

The term “aryloxy,” as used herein, refers to an aryl group attached tothe parent molecular moiety through an oxygen atom.

The term “aryloxyalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three aryloxy groups.

The term “aryloxycarbonyl,” as used herein, refers to an aryloxy groupattached to the parent molecular moiety through a carbonyl group.

The term “arylsulfonyl,” as used herein, refers to an aryl groupattached to the parent molecular moiety through a sulfonyl group.

The terms “Cap” and “cap” as used herein, refer to the group which isplaced on the nitrogen atom of the terminal nitrogen-containing ring,i.e., the pyrrolidine rings of the compound of Formula (I). It should beunderstood that “Cap” or “cap” can refer to the reagent used to appendthe group to the terminal nitrogen-containing ring or to the fragment inthe final product, i.e., “Cap-51” or “The Cap-51 fragment found inExample 5”.

The term “carbonyl,” as used herein, refers to —C(O)—.

The term “carboxy,” as used herein, refers to —CO₂H.

The term “cyano,” as used herein, refers to —CN.

The term “cycloalkyl,” as used herein, refers to a saturated monocyclic,hydrocarbon ring system having three to seven carbon atoms and zeroheteroatoms. Representative examples of cycloalkyl groups include, butare not limited to, cyclopropyl, cyclopentyl, and cyclohexyl. Thecycloalkyl groups of the present disclosure are optionally substitutedwith one, two, three, four, or five substituents independently selectedfrom alkoxy, alkyl, aryl, cyano, halo, haloalkoxy, haloalkyl,heterocyclyl, hydroxy, hydroxyalkyl, nitro, and —NR^(x)R^(y), whereinthe aryl and the heterocyclyl are further optionally substituted withone, two, or three substituents independently selected from alkoxy,alkyl, cyano, halo, haloalkoxy, haloalkyl, hydroxy, and nitro.

The term “(cycloalkyl)alkenyl,” as used herein, refers to an alkenylgroup substituted with one, two, or three cycloalkyl groups.

The term “(cycloalkyl)alkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three cycloalkyl groups. The alkyl part ofthe (cycloalkyl)alkyl is further optionally substituted with one or twogroups independently selected from hydroxy and —NR^(c)R^(d).

The term “cycloalkyloxy,” as used herein, refers to a cycloalkyl groupattached to the parent molecular moiety through an oxygen atom.

The term “cycloalkyloxyalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three cycloalkyloxy groups.

The term “cycloalkylsulfonyl,” as used herein, refers to a cycloalkylgroup attached to the parent molecular moiety through a sulfonyl group.

The term “formyl,” as used herein, refers to —CHO.

The terms “halo” and “halogen,” as used herein, refer to F, Cl, Br, orI.

The term “haloalkoxy,” as used herein, refers to a haloalkyl groupattached to the parent molecular moiety through an oxygen atom.

The term “haloalkoxycarbonyl,” as used herein, refers to a haloalkoxygroup attached to the parent molecular moiety through a carbonyl group.

The term “haloalkyl,” as used herein, refers to an alkyl groupsubstituted by one, two, three, or four halogen atoms.

The term “heterocyclyl,” as used herein, refers to a four-, five-, six-,or seven-membered ring containing one, two, three, or four heteroatomsindependently selected from nitrogen, oxygen, and sulfur. Thefour-membered ring has zero double bonds, the five-membered ring haszero to two double bonds, and the six- and seven-membered rings havezero to three double bonds. The term “heterocyclyl” also includesbicyclic groups in which the heterocyclyl ring is fused to anothermonocyclic heterocyclyl group, or a four- to six-membered aromatic ornon-aromatic carbocyclic ring; as well as bridged bicyclic groups suchas 7-azabicyclo[2.2.1]hept-7-yl, 2-azabicyclo[2.2.2]oc-2-tyl, and2-azabicyclo[2.2.2]oc-3-tyl. The heterocyclyl groups of the presentdisclosure can be attached to the parent molecular moiety through anycarbon atom or nitrogen atom in the group. Examples of heterocyclylgroups include, but are not limited to, benzothienyl, furyl, imidazolyl,indolinyl, indolyl, isothiazolyl, isoxazolyl, morpholinyl, oxazolyl,piperazinyl, piperidinyl, pyrazolyl, pyridinyl, pyrrolidinyl,pyrrolopyridinyl, pyrrolyl, thiazolyl, thienyl, thiomorpholinyl,7-azabicyclo[2.2.1]hept-7-yl, 2-azabicyclo[2.2.2]oc-2-tyl, and2-azabicyclo[2.2.2]oc-3-tyl. The heterocyclyl groups of the presentdisclosure are optionally substituted with one, two, three, four, orfive substituents independently selected from alkoxy, alkoxyalkyl,alkoxycarbonyl, alkyl, alkylcarbonyl, aryl, arylalkyl, arylcarbonyl,cyano, halo, haloalkoxy, haloalkyl, a second heterocyclyl group,heterocyclylalkyl, heterocyclylcarbonyl, hydroxy, hydroxyalkyl, nitro,—NR^(x)R^(y), (NR^(x)R^(y))alkyl, and oxo, wherein the alkyl part of thearylalkyl and the heterocyclylalkyl are unsubstituted and wherein thearyl, the aryl part of the arylalkyl, the aryl part of the arylcarbonyl,the second heterocyclyl group, and the heterocyclyl part of theheterocyclylalkyl and the heterocyclylcarbonyl are further optionallysubstituted with one, two, or three substituents independently selectedfrom alkoxy, alkyl, cyano, halo, haloalkoxy, haloalkyl, and nitro.

The term “heterocyclylalkenyl,” as used herein, refers to an alkenylgroup substituted with one, two, or three heterocyclyl groups.

The term “heterocyclylalkoxy,” as used herein, refers to a heterocyclylgroup attached to the parent molecular moiety through an alkoxy group.

The term “heterocyclylalkoxycarbonyl,” as used herein, refers to aheterocyclylalkoxy group attached to the parent molecular moiety througha carbonyl group.

The term “heterocyclylalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three heterocyclyl groups. The alkyl partof the heterocyclylalkyl is further optionally substituted with one ortwo additional groups independently selected from alkoxy,alkylcarbonyloxy, aryl, halo, haloalkoxy, haloalkyl, hydroxy, and—NR^(c)R^(d), wherein the aryl is further optionally substituted withone or two substituents independently selected from alkoxy, alkyl,unsubstituted aryl, unsubstituted arylalkoxy, unsubstitutedarylalkoxycarbonyl, halo, haloalkoxy, haloalkyl, hydroxy, and—NR^(x)R^(y).

The term “heterocyclylalkylcarbonyl,” as used herein, refers to aheterocyclylalkyl group attached to the parent molecular moiety througha carbonyl group.

The term “heterocyclylcarbonyl,” as used herein, refers to aheterocyclyl group attached to the parent molecular moiety through acarbonyl group.

The term “heterocyclyloxy,” as used herein, refers to a heterocyclylgroup attached to the parent molecular moiety through an oxygen atom.

The term “heterocyclyloxyalkyl,” as used herein, refers to an alkylgroup substituted with one, two, or three heterocyclyloxy groups.

The term “heterocyclyloxycarbonyl,” as used herein, refers to aheterocyclyloxy group attached to the parent molecular moiety through acarbonyl group.

The term “hydroxy,” as used herein, refers to —OH.

The term “hydroxyalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three hydroxy groups.

The term “hydroxyalkylcarbonyl,” as used herein, refers to ahydroxyalkyl group attached to the parent molecular moiety through acarbonyl group.

The term “nitro,” as used herein, refers to —NO₂.

The term “—NR^(a)R^(b),” as used herein, refers to two groups, R^(a) andR^(b), which are attached to the parent molecular moiety through anitrogen atom. R^(a) and R^(b) are independently selected from hydrogen,alkenyl, and alkyl.

The term “(NR^(a)R^(b))alkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three —NR^(a)R^(b) groups.

The term “(NR^(a)R^(b))carbonyl,” as used herein, refers to an—NR^(a)R^(b) group attached to the parent molecular moiety through acarbonyl group.

The term “—NR^(c)R^(d),” as used herein, refers to two groups, R^(c) andR^(d), which are attached to the parent molecular moiety through anitrogen atom. R^(c) and R^(d) are independently selected from hydrogen,alkenyloxycarbonyl, alkoxyalkylcarbonyl, alkoxycarbonyl, alkyl,alkylcarbonyl, alkylsulfonyl, aryl, arylalkoxycarbonyl, arylalkyl,arylalkylcarbonyl, arylcarbonyl, aryloxycarbonyl, arylsulfonyl,cycloalkyl, cycloalkylsulfonyl, formyl, haloalkoxycarbonyl,heterocyclyl, heterocyclylalkoxycarbonyl, heterocyclylalkyl,heterocyclylalkylcarbonyl, heterocyclylcarbonyl,heterocyclyloxycarbonyl, hydroxyalkylcarbonyl, (NR^(e)R^(f))alkyl,(NR^(e)R^(f))alkylcarbonyl, (NR^(e)R^(f))carbonyl,(NR^(e)R^(f))sulfonyl, —C(NCN)OR′, and —C(NCN)NR^(x)R^(y), wherein R′ isselected from alkyl and unsubstituted phenyl, and wherein the alkyl partof the arylalkyl, the arylalkylcarbonyl, the heterocyclylalkyl, and theheterocyclylalkylcarbonyl are further optionally substituted with one—NR^(e)R^(f) group; and wherein the aryl, the aryl part of thearylalkoxycarbonyl, the arylalkyl, the arylalkylcarbonyl, thearylcarbonyl, the aryloxycarbonyl, and the arylsulfonyl, theheterocyclyl, and the heterocyclyl part of theheterocyclylalkoxycarbonyl, the heterocyclylalkyl, theheterocyclylalkylcarbonyl, the heterocyclylcarbonyl, and theheterocyclyloxycarbonyl are further optionally substituted with one,two, or three substituents independently selected from alkoxy, alkyl,cyano, halo, haloalkoxy, haloalkyl, and nitro.

The term “(NR^(c)R^(d))alkenyl,” as used herein, refers to an alkenylgroup substituted with one, two, or three —NR^(c)R^(d) groups.

The term “(NR^(c)R^(d))alkyl-,” as used herein, refers to an alkyl groupsubstituted with one, two, or three —NR^(c)R^(d) groups. The alkyl partof the (NR^(c)R^(d))alkyl is further optionally substituted with one ortwo additional groups selected from alkoxy, alkoxyalkylcarbonyl,alkoxycarbonyl, alkylsulfanyl, arylalkoxyalkylcarbonyl, carboxy,heterocyclyl, heterocyclylcarbonyl, hydroxy, and (NR^(e)R^(f))carbonyl;wherein the heterocyclyl is further optionally substituted with one,two, three, four, or five substituents independently selected fromalkoxy, alkyl, cyano, halo, haloalkoxy, haloalkyl, and nitro.

The term “(NR^(c)R^(d))carbonyl,” as used herein, refers to an—NR^(c)R^(d) group attached to the parent molecular moiety through acarbonyl group.

The term “—NR^(e)R^(f),” as used herein, refers to two groups, R^(e) andR^(f) which are attached to the parent molecular moiety through anitrogen atom. R^(e) and R^(f) are independently selected from hydrogen,alkyl, unsubstituted aryl, unsubstituted arylalkyl, unsubstitutedcycloalkyl, unsubstituted (cyclolalkyl)alkyl, unsubstitutedheterocyclyl, unsubstituted heterocyclylalkyl, (NR^(x)R^(y))alkyl, andR^(x)R^(y))carbonyl.

The term “NR^(e)R^(f))alkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three —NR^(e)R^(f) groups.

The term “(NR^(e)R^(f))alkylcarbonyl,” as used herein, refers to an(NR^(e)R^(f))alkyl group attached to the parent molecular moiety througha carbonyl group.

The term “(NR^(e)R^(f))carbonyl,” as used herein, refers to an—NR^(e)R^(f) group attached to the parent molecular moiety through acarbonyl group.

The term “(NR^(e)R^(f))sulfonyl,” as used herein, refers to an—NR^(e)R^(f) group attached to the parent molecular moiety through asulfonyl group.

The term “—NR^(x)R^(y),” as used herein, refers to two groups, R^(x) andR^(y), which are attached to the parent molecular moiety through anitrogen atom. R^(x) and R^(y) are independently selected from hydrogen,alkoxycarbonyl, alkyl, alkylcarbonyl, unsubstituted aryl, unsubstitutedarylalkoxycarbonyl, unsubstituted arylalkyl, unsubstituted cycloalkyl,unsubstituted heterocyclyl, and (NR^(x′)R^(y′)) carbonyl, wherein R^(x′)and R^(y′) are independently selected from hydrogen and alkyl.

The term “(NR^(x)R^(y))alkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three —NR^(x)R^(y) groups.

The term “(NR^(x)R^(y))carbonyl,” as used herein, refers to an—NR^(x)R^(y) group attached to the parent molecular moiety through acarbonyl group.

The term “oxo,” as used herein, refers to ═O.

The term “sulfonyl,” as used herein, refers to —SO₂—.

The term “trialkylsilyl,” as used herein, refers to —SiR₃, wherein R isalkyl. The R groups may be the same or different.

The term “trialkylsilylalkyl,” as used herein, refers to an alkyl groupsubstituted with one, two, or three trialkylsilyl groups.

The term “trialkylsilylalkoxy,” as used herein, refers to atrialkylsilylalkyl group attached to the parent molecular moiety throughan oxygen atom.

The term “trialkylsilylalkoxyalkyl,” as used herein, refers to an alkylgroup substituted with one, two, or three trialkylsilylalkoxy groups.

Asymmetric centers exist in the compounds of the present disclosure.These centers are designated by the symbols “R” or “S”, depending on theconfiguration of substituents around the chiral carbon atom. It shouldbe understood that the disclosure encompasses all stereochemicalisomeric forms, or mixtures thereof which possess the ability to inhibitNS5A. Individual stereoisomers of compounds can be preparedsynthetically from commercially available starting materials whichcontain chiral centers or by preparation of mixtures of enantiomericproducts followed by separation such as conversion to a mixture ofdiastereomers followed by separation or recrystallization,chromatographic techniques, or direct separation of enantiomers onchiral chromatographic columns. Starting compounds of particularstereochemistry are either commercially available or can be made andresolved by techniques known in the art.

Certain compounds of the present disclosure may also exist in differentstable conformational forms which may be separable. Torsional asymmetrydue to restricted rotation about an asymmetric single bond, for examplebecause of steric hindrance or ring strain, may permit separation ofdifferent conformers. The present disclosure includes eachconformational isomer of these compounds and mixtures thereof.

The term “compounds of the present disclosure”, and equivalentexpressions, are meant to embrace compounds of Formula (I), andpharmaceutically acceptable enantiomers, diastereomers, and saltsthereof. Similarly, references to intermediates are meant to embracetheir salts where the context so permits.

The compounds of the present disclosure can exist as pharmaceuticallyacceptable salts. The term “pharmaceutically acceptable salt,” as usedherein, represents salts or zwitterionic forms of the compounds of thepresent disclosure which are water or oil-soluble or dispersible, whichare, within the scope of sound medical judgment, suitable for use incontact with the tissues of patients without excessive toxicity,irritation, allergic response, or other problem or complicationcommensurate with a reasonable benefit/risk ratio, and are effective fortheir intended use The salts can be prepared during the final isolationand purification of the compounds or separately by reacting a suitablenitrogen atom with a suitable acid. Representative acid addition saltsinclude acetate, adipate, alginate, citrate, aspartate, benzoate,benzenesulfonate, bisulfate, butyrate, camphorate, camphorsulfonate;digluconate, dihydrobromide, dihydrochloride, dihydroiodide,glycerophosphate, hemisulfate, heptanoate, hexanoate, formate, fumarate,hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethanesulfonate,lactate, maleate, mesitylenesulfonate, methanesulfonate,naphthylenesulfonate, nicotinate, 2-naphthalenesulfonate, oxalate,palmoate, pectinate, persulfate, 3-phenylproprionate, picrate, pivalate,propionate, succinate, tartrate, trichloroacetate, trifluoroacetate,phosphate, glutamate, bicarbonate, para-toluenesulfonate, andundecanoate. Examples of acids which can be employed to formpharmaceutically acceptable addition salts include inorganic acids suchas hydrochloric, hydrobromic, sulfuric, and phosphoric, and organicacids such as oxalic, maleic, succinic, and citric.

Basic addition salts can be prepared during the final isolation andpurification of the compounds by reacting a carboxy group with asuitable base such as the hydroxide, carbonate, or bicarbonate of ametal cation or with ammonia or an organic primary, secondary, ortertiary amine. The cations of pharmaceutically acceptable salts includelithium, sodium, potassium, calcium, magnesium, and aluminum, as well asnontoxic quaternary amine cations such as ammonium, tetramethylammonium,tetraethylammonium, methylamine, dimethylamine, trimethylamine,triethylamine, diethylamine, ethylamine, tributylamine, pyridine,N,N-dimethylaniline, N-methylpiperidine, N-methylmorpholine,dicyclohexylamine, procaine, dibenzylamine, N,N-dibenzylphenethylamine,and N,N′-dibenzylethylenediamine. Other representative organic aminesuseful for the formation of base addition salts include ethylenediamine,ethanolamine, diethanolamine, piperidine, and piperazine.

When it is possible that, for use in therapy, therapeutically effectiveamounts of a compound of Formula (I), as well as pharmaceuticallyacceptable salts thereof, may be administered as the raw chemical, it ispossible to present the active ingredient as a pharmaceuticalcomposition. Accordingly, the disclosure further provides pharmaceuticalcompositions, which include therapeutically effective amounts ofcompounds of Formula (I) or pharmaceutically acceptable salts thereof,and one or more pharmaceutically acceptable carriers, diluents, orexcipients. The term “therapeutically effective amount,” as used herein,refers to the total amount of each active component that is sufficientto show a meaningful patient benefit, e.g., a reduction in viral load.When applied to an individual active ingredient, administered alone, theterm refers to that ingredient alone. When applied to a combination, theterm refers to combined amounts of the active ingredients that result inthe therapeutic effect, whether administered in combination, serially,or simultaneously. The compounds of Formula (I) and pharmaceuticallyacceptable salts thereof, are as described above. The carrier(s),diluent(s), or excipient(s) must be acceptable in the sense of beingcompatible with the other ingredients of the formulation and notdeleterious to the recipient thereof. In accordance with another aspectof the present disclosure there is also provided a process for thepreparation of a pharmaceutical formulation including admixing acompound of Formula (I), or a pharmaceutically acceptable salt thereof,with one or more pharmaceutically acceptable carriers, diluents, orexcipients. The term “pharmaceutically acceptable,” as used herein,refers to those compounds, materials, compositions, and/or dosage formswhich are, within the scope of sound medical judgment, suitable for usein contact with the tissues of patients without excessive toxicity,irritation, allergic response, or other problem or complicationcommensurate with a reasonable benefit/risk ratio, and are effective fortheir intended use.

Pharmaceutical formulations may be presented in unit dose formscontaining a predetermined amount of active ingredient per unit dose.Dosage levels of between about 0.01 and about 250 milligram per kilogram(“mg/kg”) body weight per day, preferably between about 0.05 and about100 mg/kg body weight per day of the compounds of the present disclosureare typical in a monotherapy for the prevention and treatment of HCVmediated disease. Typically, the pharmaceutical compositions of thisdisclosure will be administered from about 1 to about 5 times per day oralternatively, as a continuous infusion. Such administration can be usedas a chronic or acute therapy. The amount of active ingredient that maybe combined with the carrier materials to produce a single dosage formwill vary depending on the condition being treated, the severity of thecondition, the time of administration, the route of administration, therate of excretion of the compound employed, the duration of treatment,and the age, gender, weight, and condition of the patient. Preferredunit dosage formulations are those containing a daily dose or sub-dose,as herein above recited, or an appropriate fraction thereof of an activeingredient. Treatment may be initiated with small dosages substantiallyless than the optimum dose of the compound. Thereafter, the dosage isincreased by small increments until the optimum effect under thecircumstances is reached. In general, the compound is most desirablyadministered at a concentration level that will generally affordantivirally effective results without causing any harmful or deleteriousside effects.

When the compositions of this disclosure comprise a combination of acompound of the present disclosure and one or more additionaltherapeutic or prophylactic agent, both the compound and the additionalagent are usually present at dosage levels of between about 10 to 150%,and more preferably between about 10 and 80% of the dosage normallyadministered in a monotherapy regimen.

Pharmaceutical formulations may be adapted for administration by anyappropriate route, for example by the oral (including buccal orsublingual), rectal, nasal, topical (including buccal, sublingual, ortransdermal), vaginal, or parenteral (including subcutaneous,intracutaneous, intramuscular, intra-articular, intrasynovial,intrasternal, intrathecal, intralesional, intravenous, or intradermalinjections or infusions) route. Such formulations may be prepared by anymethod known in the art of pharmacy, for example by bringing intoassociation the active ingredient with the carrier(s) or excipient(s).Oral administration or administration by injection are preferred.

Pharmaceutical formulations adapted for oral administration may bepresented as discrete units such as capsules or tablets; powders orgranules; solutions or suspensions in aqueous or non-aqueous liquids;edible foams or whips; or oil-in-water liquid emulsions or water-in-oilemulsions.

For instance, for oral administration in the form of a tablet orcapsule, the active drug component can be combined with an oral,non-toxic pharmaceutically acceptable inert carrier such as ethanol,glycerol, Water, and the like. Powders are prepared by comminuting thecompound to a suitable fine size and mixing with a similarly comminutedpharmaceutical carrier such as an edible carbohydrate, as, for example,starch or mannitol. Flavoring, preservative, dispersing, and coloringagent can also be present.

Capsules are made by preparing a powder mixture, as described above, andfilling formed gelatin sheaths. Glidants and lubricants such ascolloidal silica, talc, magnesium stearate, calcium stearate, or solidpolyethylene glycol can be added to the powder mixture before thefilling operation. A disintegrating or solubilizing agent such asagar-agar, calcium carbonate, or sodium carbonate can also be added toimprove the availability of the medicament when the capsule is ingested.

Moreover, when desired or necessary, suitable binders, lubricants,disintegrating agents, and coloring agents can also be incorporated intothe mixture. Suitable binders include starch, gelatin, natural sugarssuch as glucose or beta-lactose, corn sweeteners, natural and syntheticgums such as acacia, tragacanth or sodium alginate,carboxymethylcellulose, polyethylene glycol, and the like. Lubricantsused in these dosage forms include sodium oleate, sodium chloride, andthe like. Disintegrators include, without limitation, starch, methylcellulose, agar, betonite, xanthan gum, and the like. Tablets areformulated, for example, by preparing a powder mixture, granulating orslugging, adding a lubricant and disintegrant, and pressing intotablets. A powder mixture is prepared by mixing the compound, suitablecomminuted, with a diluent or base as described above, and optionally,with a binder such as carboxymethylcellulose, an aliginate, gelating, orpolyvinyl pyrrolidone, a solution retardant such as paraffin, aresorption accelerator such as a quaternary salt and/or and absorptionagent such as betonite, kaolin, or dicalcium phosphate. The powdermixture can be granulated by wetting with a binder such as syrup, starchpaste, acadia mucilage, or solutions of cellulosic or polymericmaterials and forcing through a screen. As an alternative togranulating, the powder mixture can be run through the tablet machineand the result is imperfectly formed slugs broken into granules. Thegranules can be lubricated to prevent sticking to the tablet formingdies by means of the addition of stearic acid, a stearate salt, talc, ormineral oil. The lubricated mixture is then compressed into tablets. Thecompounds of the present disclosure can also be combined with a freeflowing inert carrier and compressed into tablets directly without goingthrough the granulating or slugging steps. A clear or opaque protectivecoating consisting of a sealing coat of shellac, a coating of sugar orpolymeric material, and a polish coating of wax can be provided.Dyestuffs can be added to these coatings to distinguish different unitdosages.

Oral fluids such as solution, syrups, and elixirs can be prepared indosage unit form so that a given quantity contains a predeterminedamount of the compound. Syrups can be prepared by dissolving thecompound in a suitably flavored aqueous solution, while elixirs areprepared through the use of a non-toxic vehicle. Solubilizers andemulsifiers such as ethoxylated isostearyl alcohols and polyoxyethylenesorbitol ethers, preservatives, flavor additive such as peppermint oilor natural sweeteners, or saccharin or other artificial sweeteners, andthe like can also be added.

Where appropriate, dosage unit formulations for oral administration canbe microencapsulated. The formulation can also be prepared to prolong orsustain the release as for example by coating or embedding particulatematerial in polymers, wax, or the like.

The compounds of Formula (I), and pharmaceutically acceptable saltsthereof, can also be administered in the form of liposome deliverysystems, such as small unilamellar vesicles, large unilamellar vesicles,and multilamellar vesicles. Liposomes can be formed from a variety ofphopholipids, such as cholesterol, stearylamine, or phophatidylcholines.

The compounds of Formula (I) and pharmaceutically acceptable saltsthereof may also be delivered by the use of monoclonal antibodies asindividual carriers to which the compound molecules are coupled. Thecompounds may also be coupled with soluble polymers as targetable drugcarriers. Such polymers can include polyvinylpyrrolidone, pyrancopolymer, polyhydroxypropylmethaerylamidephenol,polyhydroxyethylaspartamidephenol, or polyethyleneoxidepolylysinesubstituted with palitoyl residues. Furthermore, the compounds may becoupled to a class of biodegradable polymers useful in achievingcontrolled release of a drug, for example, polylactic acid, polepsiloncaprolactone, polyhydroxy butyric acid, polyorthoesters, polyacetals,polydihydropyrans, polycyanoacrylates, and cross-linked or amphipathicblock copolymers of hydrogels.

Pharmaceutical formulations adapted for transdermal administration maybe presented as discrete patches intended to remain in intimate contactwith the epidermis of the recipient for a prolonged period of time. Forexample, the active ingredient may be delivered from the patch byiontophoresis as generally described in Pharmaceutical Research 1986,3(6), 318.

Pharmaceutical formulations adapted for topical administration may beformulated as ointments, creams, suspensions, lotions, powders,solutions, pastes, gels, sprays, aerosols, or oils.

Pharmaceutical formulations adapted for rectal administration may bepresented as suppositories or as enemas.

Pharmaceutical formulations adapted for nasal administration wherein thecarrier is a solid include a course powder having a particle size forexample in the range 20 to 500 microns which is administered in themanner in which snuff is taken, i.e., by rapid inhalation through thenasal passage from a container of the powder held close up to the nose.Suitable formulations wherein the carrier is a liquid, foradministration as a nasal spray or nasal drops, include aqueous or oilsolutions of the active ingredient.

Pharmaceutical formulations adapted for administration by inhalationinclude fine particle dusts or mists, which may be generated by means ofvarious types of metered, dose pressurized aerosols, nebulizers, orinsufflators.

Pharmaceutical formulations adapted for vaginal administration may bepresented as pessaries, tampons, creams, gels, pastes, foams, or sprayformulations.

Pharmaceutical formulations adapted for parenteral administrationinclude aqueous and non-aqueous sterile injection solutions which maycontain anti-oxidants, buffers, bacteriostats, and soutes which renderthe formulation isotonic with the blood of the intended recipient; andaqueous and non-aqueous sterile suspensions which may include suspendingagents and thickening agents. The formulations may be presented inunit-dose or multi-dose containers, for example sealed ampoules andvials, and may be stored in a freeze-dried (lyophilized) conditionrequiring only the addition of the sterile liquid carrier, for examplewater for injections, immediately prior to use. Extemporaneous injectionsolutions and suspensions may be prepared from sterile powders,granules, and tablets.

It should be understood that in addition to the ingredients particularlymentioned above, the formulations may include other agents conventionalin the art having regard to the type of formulation in question, forexample those suitable for oral administration may include flavoringagents.

The term “patient” includes both human and other mammals.

The term “treating” refers to: (i) preventing a disease, disorder orcondition from occurring in a patient that may be predisposed to thedisease, disorder, and/or condition but has not yet been diagnosed ashaving it; (ii) inhibiting the disease, disorder, or condition, i.e.,arresting its development; and (iii) relieving the disease, disorder, orcondition, i.e., causing regression of the disease, disorder, and/orcondition.

The compounds of the present disclosure can also be administered with acyclosporin, for example, cyclosporin A. Cyclosporin A has been shown tobe active against HCV in clinical trials (Hepatology 2003, 38, 1282;Biochem. Biophys. Res. Commun. 2004, 313, 42; J. Gastroenterol. 2003,38, 567).

Table 1 below lists some illustrative examples of compounds that can beadministered with the compounds of this disclosure. The compounds of thedisclosure can be administered with other anti-HCV activity compounds incombination therapy, either jointly or separately, or by combining thecompounds into a composition.

TABLE 1 Type of Inhibitor or Brand Name Physiological Class TargetSource Company NIM811 Cyclophilin Inhibitor Novartis ZadaxinImmuno-modulator Sciclone Suvus Methylene blue Bioenvision Actilon TLR9agonist Coley (CPG10101) Batabulin (T67) Anticancer β-tubulin inhibitorTularik Inc., South San Francisco, CA ISIS 14803 Antiviral antisenseISIS Pharmaceuticals Inc, Carlsbad, CA/Elan Phamaceuticals Inc., NewYork, NY Summetrel Antiviral antiviral Endo Pharmaceuticals HoldingsInc., Chadds Ford, PA GS-9132 (ACH- Antiviral HCV InhibitorAchillion/Gilead 806) Pyrazolopyrimidine Antiviral HCV Inhibitors ArrowTherapeutics compounds and Ltd. salts From WO- 2005047288 26 May 2005Levovirin Antiviral IMPDH inhibitor Ribapharm Inc., Costa Mesa, CAMerimepodib Antiviral IMPDH inhibitor Vertex (VX-497) PharmaceuticalsInc., Cambridge, MA XTL-6865 (XTL- Antiviral monoclonal antibody XTL002) Biopharmaceuticals Ltd., Rehovot, Isreal Telaprevir Antiviral NS3serine protease Vertex (VX-950, LY- inhibitor Pharmaceuticals 570310)Inc., Cambridge, MA/Eli Lilly and Co. Inc., Indianapolis, IN HCV-796Antiviral NS5B Replicase Wyeth/Viropharma Inhibitor NM-283 AntiviralNS5B Replicase Idenix/Novartis Inhibitor GL-59728 Antiviral NS5BReplicase Gene Labs/Novartis Inhibitor GL-60667 Antiviral NS5B ReplicaseGene Labs/Novartis Inhibitor 2′C MeA Antiviral NS5B Replicase GileadInhibitor PSI 6130 Antiviral NS5B Replicase Roche Inhibitor R1626Antiviral NS5B Replicase Roche Inhibitor 2′C Methyl Antiviral NS5BReplicase Merck adenosine Inhibitor JTK-003 Antiviral RdRp inhibitorJapan Tobacco Inc., Tokyo, Japan Levovirin Antiviral ribavirin ICNPharmaceuticals, Costa Mesa, CA Ribavirin Antiviral ribavirinSchering-Plough Corporation, Kenilworth, NJ Viramidine AntiviralRibavirin Prodrug Ribapharm Inc., Costa Mesa, CA Heptazyme Antiviralribozyme Ribozyme Pharmaceuticals Inc., Boulder, CO BILN-2061 Antiviralserine protease Boehringer inhibitor Ingelheim Pharma KG, Ingelheim,Germany SCH 503034 Antiviral serine protease Schering Plough inhibitorZadazim Immune modulator Immune modulator SciClone Pharmaceuticals Inc.,San Mateo, CA Ceplene Immunomodulator immune modulator MaximPharmaceuticals Inc., San Diego, CA CellCept Immunosuppressant HCV IgGimmuno- F, Hoffmann-La suppressant Roche LTD, Basel, Switzerland CivacirImmunosuppressant HCV IgG immuno- Nabi suppressant BiopharmaceuticalsInc., Boca Raton, FL Albuferon - α Interferon albumin IFN-α2b HumanGenome Sciences Inc., Rockville, MD Infergen A Interferon IFN InterMunealfacon-1 Pharmaceuticals Inc., Brisbane, CA Omega IFN Interferon IFN-ωIntarcia Therapeutics IFN-β and EMZ701 Interferon IFN-β and EMZ701Transition Therapeutics Inc., Ontario, Canada Rebif Interferon IFN-β1aSerono, Geneva, Switzerland Roferon A Interferon IFN-α2a F. Hoffmann-LaRoche LTD, Basel, Switzerland Intron A Interferon IFN-α2bSchering-Plough Corporation, Kenilworth, NJ Intron A and InterferonIFN-α2b/α1-thymosin RegeneRx Zadaxin Biopharma. Inc., Bethesda, MD/SciClone Pharmaceuticals Inc, San Mateo, CA Rebetron InterferonIFN-α2b/ribavirin Schering-Plough Corporation, Kenilworth, NJ ActimmuneInterferon INF-γ InterMune Inc., Brisbane, CA Interferon-β InterferonInterferon-β-1a Serono Multiferon Interferon Long lasting IFNViragen/Valentis Wellferon Interferon Lympho-blastoid IFN-GlaxoSmithKline αn1 plc, Uxbridge, UK Omniferon Interferon natural IFN-αViragen Inc., Plantation, FL Pegasys Interferon PEGylated IFN-α2a F.Hoffmann-La Roche LTD, Basel, Switzerland Pegasys and InterferonPEGylated IFN-α2a/ Maxim Ceplene immune modulator Pharmaceuticals Inc.,San Diego, CA Pegasys and Interferon PEGylated IFN- F. Hoffmann-LaRibavirin α2a/ribavirin Roche LTD, Basel, Switzerland PEG-IntronInterferon PEGylated IFN-α2b Schering-Plough Corporation, Kenilworth, NJPEG-Intron/ Interferon PEGylated IFN- Schering-Plough Ribavirinα2b/ribavirin Corporation, Kenilworth, NJ IP-501 Liver protectionantifibrotic Indevus Pharmaceuticals Inc., Lexington, MA IDN-6556 Liverprotection caspase inhibitor Idun Pharmaceuticals Inc., San Diego, CAITMN-191 (R-7227) Antiviral serine protease InterMune inhibitorPharmaceuticals Inc., Brisbane, CA GL-59728 Antiviral NS5B ReplicaseGenelabs Inhibitor ANA-971 Antiviral TLR-7 agonist Anadys BoceprevirAntiviral serine protease Schering Plough inhibitor TMS-435 Antiviralserine protease Tibotec BVBA, inhibitor Mechelen, Belgium BI-201335Antiviral serine protease Boehringer inhibitor Ingelheim Pharma KG,Ingelheim, Germany MK-7009 Antiviral serine protease Merck inhibitorPF-00868554 Antiviral replicase inhibitor Pfizer ANA598 AntiviralNon-Nucleoside Anadys NS5B Polymerase Pharmaceuticals, Inhibitor Inc.,San Diego, CA, USA IDX375 Antiviral Non-Nucleoside Idenix ReplicaseInhibitor Pharmaceuticals, Cambridge, MA, USA BILB 1941 Antiviral NS5BPolymerase Boehringer Inhibitor Ingelheim Canada Ltd R&D, Laval, QC,Canada PSI-7851 Antiviral Nucleoside Pharmasset, Polymerase inhibitorPrinceton, NJ, USA VCH-759 Antiviral NS5B Polymerase ViroChem PharmaInhibitor VCH-916 Antiviral NS5B Polymerase ViroChem Pharma InhibitorGS-9190 Antiviral NS5B Polymerase Gilead Inhibitor Peg-interferonAntiviral Interferon ZymoGenetics/ lamda Bristol-Myers Squibb

The compounds of the present disclosure may also be used as laboratoryreagents. Compounds may be instrumental in providing research tools fordesigning of viral replication assays, validation of animal assaysystems and structural biology studies to further enhance knowledge ofthe HCV disease mechanisms. Further, the compounds of the presentdisclosure are useful in establishing or determining the binding site ofother antiviral compounds, for example, by competitive inhibition.

The compounds of this disclosure may also be used to treat or preventviral contamination of materials and therefore reduce the risk of viralinfection of laboratory or medical personnel or patients who come incontact with such materials, e.g., blood, tissue, surgical instrumentsand garments, laboratory instruments and garments, and blood collectionor transfusion apparatuses and materials.

This disclosure is intended to encompass compounds having Formula (I)when prepared by synthetic processes or by metabolic processes includingthose occurring in the human or animal body (in vivo) or processesoccurring in vitro.

The abbreviations used in the present application, includingparticularly in the illustrative schemes and examples which follow, arewell-known to those skilled in the art. Some of the abbreviations usedare as follows: t-butyl for tert-butyl; HATU for HATU forO-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate; Boc or BOC for tert-butoxycarbonyl; NBS forN-bromosuccinimide; DMSO for dimethylsulfoxide; MeOH for methanol; TFAfor trifluoroacetic acid; THF for tetrahydrofuran; DMAP for4-dimethylaminopyridine; EDCI for1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride; RT for roomtemperature or retention time (context will dictate); t_(R) forretention time; DEA for diethylamine; NH₄OAc for ammonium acetate;t-Bu₃P for tri-tert-butylphosphine; HMDS for hexamethyldisilazide; DMFfor N,N-dimethylformamide; EtOAC, EtOAc, or EA for ethyl acetate; Et₃Nor TEA for triethylamine; MeI for methyl iodide; DIBAL for diisobutylaluminum hydride; TBDMSCl for tert-butyldimethylsilyl chloride; iPrOH ori-PrOH for isopropanol; Bn for benzyl; Hex for hexanes; and PPh₃ fortriphenylphosphine.

The compounds and processes of the present disclosure will be betterunderstood in connection with the following synthetic schemes whichillustrate the methods by which the compounds of the present disclosuremay be prepared. Starting materials can be obtained from commercialsources or prepared by well-established literature methods known tothose of ordinary skill in the art. It will be readily apparent to oneof ordinary skill in the art that the compounds defined above can besynthesized by substitution of the appropriate reactants and agents inthe syntheses shown below. It will also be readily apparent to oneskilled in the art that the selective protection and deprotection steps,as well as the order of the steps themselves, can be carried out invarying order, depending on the nature of the variables to successfullycomplete the syntheses below. The variables are as defined above unlessotherwise noted below.

Scheme 1

Heating chloride 1 with NHR¹R^(q) in the presence of a base such asHunig's base could afford bromide 2, which could be coupled withboronate ester 3 under standard Suzuki-Miayura coupling condition. Itshould be noted that the boronic acid analog of 3 may be used in placeof the boronate ester. Deprotection of the pyrrolidine group of 4, inthe case where R^(f)=t-butyl, could be accomplished by treatment withstrong acid such as HCl or trifluoroacetic acid. Acylation of 5 can beaccomplished under standard acylation conditions. A coupling reagentsuch as HATU in combination with an amine base such as Hunig's base canbe used in this regard. Alternatively, 5 may be reacted with isocyanatesor carbamoyl chlorides to provide compounds of formula 6 where R¹¹ is anamine. Pyrrolidine 5 can also be reacted with chloroformates to afford 6where R¹¹ is an alcohol.

Compound 6 wherein R⁷ is —CH(NHBoc)R⁹ can be converted to 7 viatreatment with strong acid such as HCl or trifluoroacetic acid. Amine 7could be acylated under coupling conditions such as HATU/Hunig's base toafford amide 8a. Treatment of amine 7 with appropriate chloroformate,isocyanate or carbamoyl chloride, or sulfonyl chloride affords compounds8b, 8c or 8d respectively.

Compounds 9 and 10 could be prepared according to Scheme 1 and Scheme 2by employing appropriate analogs of 1 such as chlorides 11-19, 25(Scheme 4) and 28 (Scheme 4). Substrates 11-16 could be obtained fromcommercial sources, whereas substrates 17-19 could be prepared accordingto literature protocols (Australian Journal of Chemistry 1984, 37, 1065for 17; Journal of Heterocyclic Chemistry 1972, 9, 1151 and referencescited therein for 18-19).

Substrates 25 and 28 could be prepared according Scheme 4. Condensationof pyridine 20 with an alkoxymethylene malonate, such as dimethyl2-(methoxymethylene) malonate, could afford pyridine 21. Pyridine 21could be cyclized to 22 by heating in various solvents such as diphenylether. The sequential saponifications and decarboxylation of 22 could beaccomplished by heating it at high temperature in the presence of a basesuch as NaOH. The conversion of 24 to 25 could be accomplished bytreatment with reactants such as POCl₃. The treatment of ester 26 withformimidamide, accompanied with heating, could afford 27, which in turncould be converted to 28 by treatment with substrates such as POCl₃.

It should be noted that treatment of substrates 11-19, 25 and 28 withR¹R^(q)NH, as described for substrate 1 in Scheme 1, is likely to resultin a selective aminolysis at C*. In the cases where aminolysis resultsin regioisomeric mixture of products, isolation of the desired productcould be effected by employing various standard techniques known tothose of ordinary skill in the art.

Scheme 5

Scheme 5 describes the preparation of the boronate ester employed inSchemes 1. Key intermediate 30 is prepared from keto-amide 29 orketo-ester 32 via heating with ammonium acetate under thermal ormicrowave conditions. Keto-amide 29 can be prepared from 28 viacondensation with an appropriate amino acid under standard amideformation conditions. Bromide 31 can give rise to 28 by treatment with anucleophile such as azide followed by a reduction, or by treatment withphthalimide or sodium diformylamide (Synthesis 1990, 122) followed bydeprotection. Bromide 31 can also be converted to 32 by reacting with anappropriate N-protected amino acid in the presence of base such asHunig's base. Bromination of 33 with a source of bromonium ion such asbromine, or NBS results in the formation of 31. Bromide 30 can beconverted to boronic ester 3 via treatment with bis-pinacalotodiboronunder palladium catalysis according to the method described in Journalof Organic Chemistry 1995, 60, 7508, or variations thereof

Substituted phenylglycine derivatives can be prepared by a number ofmethods exemplified below. Phenylglycine t-butyl ester can bereductively alkylated (pathyway A) with an appropriate aldehyde and areductant such as sodium cyanoborohydride in acidic medium. Hydrolysisof the t-butyl ester can be accomplished with strong acid such as HCl ortrifluoroacetic acid. Alternatively, phenylglycine can be alkylated withan alkyl halide such as ethyl iodide and a base such as sodiumbicarbonate or potassium carbonate (Pathway B). Pathway C illustratesreductive alkylation of phenylglycine as in pathway A followed by asecond reductive alkylation with an alternate aldehyde such asformaldehyde in the presence of a reducing agent and acid. Pathway Dillustrates the synthesis of substituted phenylglycines via thecorresponding mandelic acid analogs. Conversion of the secondary alcoholto a competent leaving group can be accomplished with p-toluensulfonylchloride. Displacement of the tosylate group with an appropriate aminefollowed by reductive removal of the benzyl ester can providesubstituted phenylglycine derivatives. In pathway E a racemicsubstituted phenylglycine derivative is resolved by esterification withan enantiomerically pure chiral auxiliary such as but not limited to(+)-1-phenylethanol, (−)-1-phenylethanol, an Evan's oxazolidinone, orenantiomerically pure pantolactone. Separation of the diastereomers isaccomplished via chromatography (silica gel, HPLC, crystallization, etc)followed by removal of the chiral auxiliary providing enantiomericallypure phenylglycine derivatives. Pathway H illustrates a syntheticsequence which intersects with pathway E wherein the aforementionedchiral auxiliary is installed prior to amine addition. Alternatively, anester of an arylacetic acid can be brominated with a source of bromoniumion such as bromine, N-bromosuccinimide, or CBr₄. The resultant benzylicbromide can be displaced with a variety of mono- or di-substitutedamines in the presence of a tertiary amine base such as triethylamine orHunig's base. Hydrolysis of the methyl ester via treatment with lithiumhydroxide at low temperature or 6N HCl at elevated temperature providesthe substituted phenylglycine derivatives. Another method is shown inpathway G. Glycine analogs can be derivatized with a variety of arylhalides in the presence of a source of palladium (0) such as palladiumbis(tributylphosphine) and base such as potassium phosphate. Theresultant ester can then be hydrolyzed by treatment with base or acid.It should be understood that other well known methods to preparephenylglycine derivatives exist in the art and can be amended to providethe desired compounds in this description. It should also be understoodthat the final phenylglycine derivatives can be purified to enantiomericpurity greater than 98% ee via preparative HPLC using for example chiralcolumn. It is apparent to one of ordinary skill in the art theapproaches described for the synthesis of aromatic glycine derivativesis equally applicable to the synthesis glycine derivatives containingnon-aromatic group at C-2.

In another embodiment of the present disclosure, acylated glycinederivatives may be prepared as illustrated below. Glycine derivativeswherein the carboxylic acid is protected as an easily removed ester, maybe acylated with an acid chloride in the presence of a base such astriethylamine to provide the corresponding amides (pathway A). Pathway Billustrates the acylation of the starting glycine derivative with anappropriate chloroformate while pathway C shows reaction with anappropriate isocyanate or carbamoyl chloride. Each of the threeintermediates shown in pathways A-C may be deprotected by methods knownby those skilled in the art (i.e., treatment of the t-butyl ester withstrong base such as HCl or trifluoroacetic acid).

Amino-substituted phenylacetic acids may be prepared by treatment of achloromethylphenylacetic acid with an excess of an amine.

Compound Analysis Conditions

Purity assessment and low resolution mass analysis were conducted on aShimadzu LC system coupled with Waters Micromass ZQ MS system. It shouldbe noted that retention times may vary slightly between machines. The LCconditions employed in determining the retention time (RT) were:

Condition 1

Column=Phenomenex-Luna 3.0×50 mm S10

Start % B=0

Final % B=100

Gradient time=2 min

Stop time=3 min

Flow Rate=4 mL/min

Wavelength=220 nm

Solvent A=0.1% TFA in 10% methanol/90% H₂O

Solvent B=0.1% TFA in 90% methanol/10% H₂O

Condition 2

Column=Phenomenex-Luna 4.6×50 mm S10

Start % B=0

Final % B=100

Gradient time=2 min

Stop time=3 min

Flow Rate=5 mL/min

Wavelength=220 nm

Solvent A=0.1% TFA in 10% methanol/90% H₂O

Solvent B=0.1% TFA in 90% methanol/10% H₂O

Condition 3

Column=HPLC XTERRA C18 3.0×50 mm S7

Start % B=0

Final % B=100

Gradient time=3 min

Stop time=4 min

Flow Rate=4 mL/min

Wavelength=220 nm

Solvent A=0.1% TFA in 10% methanol/90% H₂O

Solvent B=0.1% TEA in 90% methanol/10% H₂O

Condition M1

Column: Luna 4.6×50 mm S10

Start % B=0

Final % B=100

Gradient time=3 min

Stop time=4 min

Flow rate=4 mL/min

Solvent A:=95% H₂O: 5% CH₃CN, 10 mm Ammonium acetate

Solvent B:=5% H₂O: 95% CH₃CN; 10 mm Ammonium acetate

Synthesis of Common Caps

A suspension of 10% Pd/C (2.0 g) in methanol (10 mL) was added to amixture of (R)-2-phenylglycine (10 g, 66.2 mmol), formaldehyde (33 mL of37% wt. in water), 1N HCl (30 mL) and methanol (30 mL), and exposed toH₂ (60 psi) for 3 hours. The reaction mixture was filtered throughdiatomaceous earth (CELITE®), and the filtrate was concentrated invacuo. The resulting crude material was recrystallized from isopropanolto provide the HCl salt of Cap-1 as a white needle (4.0 g). Opticalrotation: −117.1° [c=9.95 mg/mL in H₂O; λ=589 nm]. ¹H NMR (DMSO-d₆,δ=2.5 ppm, 500 MHz): δ 7.43-7.34 (m, 5H), 4.14 (s, 1H), 2.43 (s, 6H); LC(Cond. I): RT=0.25; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₀H₁₄NO₂ 180.10;found 180.17; HRMS: Anal. Calcd. for [M+H]⁺ C₁₀H₁₄NO₂ 180.1025; found180.1017.

NaBH₃CN (6.22 g, 94 mmol) was added in portions over a few minutes to acooled (ice/water) mixture of (R)-2-Phenylglycine (6.02 g, 39.8 mmol)and methanol (100 mL), and stirred for 5 minutes. Acetaldehyde (10 mL)was added dropwise over 10 minutes and stirring was continued at thesame cooled temperature for 45 minutes and at ambient temperature for˜6.5 hours. The reaction mixture was cooled back with ice-water bath,treated with water (3 mL) and then quenched with a dropwise addition ofconcentrated HCl over ˜45 minutes until the pH of the mixture was˜1.5-2.0. The cooling bath was removed and the stirring was continuedwhile adding concentrated HCl in order to maintain the pH of the mixturearound 1.5-2.0. The reaction mixture was stirred overnight, filtered toremove the white suspension, and the filtrate was concentrated in vacuo.The crude material was recrystallized from ethanol to afford the HClsalt of Cap-2 as a shining white solid in two crops (crop-1: 4.16 g;crop-2: 2.19 g). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): 10.44 (1.00, brs, 1H), 7.66 (m, 2H), 7.51 (m, 3H), 5.30 (s, 1H), 3.15 (br m, 2H), 2.98(br m, 2H), 1.20 (app br s, 6H). Crop-1: [α]²⁵ −102.21° (c=0.357, H₂O);crop-2: [α]²⁵ −9.7° (c=0.357, H₂O). LC (Cond. I): RT=0.43 min; LC/MS:Anal. Calcd. for [M+H]⁺ C₁₂H₁₈NO₂: 208.13; found 208.26.

Acetaldehyde (5.0 mL, 89.1 mmol) and a suspension of 10% Pd/C (720 mg)in methanol/H₂O (4 mL/1 mL) was sequentially added to a cooled (˜15° C.)mixture of (R)-2-phenylglycine (3.096 g, 20.48 mmol), 1N HCl (30 mL) andmethanol (40 mL). The cooling bath was removed and the reaction mixturewas stirred under a balloon of H₂ for 17 hours. An additionalacetaldehyde (10 mL, 178.2 mmol) was added and stirring continued underH₂ atmosphere for 24 hours [Note: the supply of H₂ was replenished asneeded throughout the reaction]. The reaction mixture was filteredthrough diatomaceous earth (CELITE®), and the filtrate was concentratedin vacuo. The resulting crude material was recrystallized fromisopropanol to provide the HCl salt of (R)-2-(ethylamino)-2-phenylaceticacid as a shining white solid (2.846 g). ¹H NMR (DMSO-d₆, δ=2.5 ppm; 400MHz): δ 14.15 (br s, 1H), 9.55 (br s, 2H), 7.55-7.48 (m, 5H), 2.88 (brm, 1H), 2.73 (br m, 1H), 1.20 (app t, J=7.2, 3H). LC (Cond. I): RT=0.39min; >95% homogeneity index; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₀H₁₄NO₂:180.10; found 180.18.

A suspension of 10% Pd/C (536 mg) in methanol/H₂O (3 mL/1 mL) was addedto a mixture of (R)-2-(ethylamino)-2-phenylacetic acid/HCl (1.492 g,6.918 mmol), formaldehyde (20 mL of 37% wt. in water), 1N HCl (20 mL)and methanol (23 mL). The reaction mixture was stirred under a balloonof H₂ for 72 hours, where the H₂ supply was replenished as needed. Thereaction mixture was filtered through diatomaceous earth (CELITE®) andthe filtrate was concentrated in vacuo. The resulting crude material wasrecrystallized from isopropanol (50 mL) to provide the HCl salt of Cap-3as a white solid (985 mg). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 10.48(br s, 1H), 7.59-7.51 (m, 5H), 5.26 (s, 1H), 3.08 (app br s, 2H), 2.65(br s, 3H), 1.24 (br m, 3H). LC (Cond. I): RT=0.39 min; >95% homogeneityindex; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₁H₁₆NO₂: 194.12; found 194.18;HRMS: Anal. Calcd. for [M+]⁺ C₁₁H₁₆NO₂: 194.1180; found 194.1181.

ClCO₂Me (3.2 mL, 41.4 mmol) was added dropwise to a cooled (ice/water)THF (410 mL) semi-solution of (R)-tert-butyl 2-amino-2-phenylacetate/HCl(9.877 g, 40.52 mmol) and diisopropylethylamine (14.2 mL, 81.52 mmol)over 6 min, and stirred at similar temperature for 5.5 hours. Thevolatile component was removed in vacuo, and the residue was partitionedbetween water (100 mL) and ethyl acetate (200 mL). The organic layer waswashed with 1N HCl (25 mL) and saturated NaHCO₃ solution (30 mL), dried(MgSO₄), filtered, and concentrated in vacuo. The resultant colorlessoil was triturated from hexanes, filtered and washed with hexanes (100mL) to provide (R)-tert-butyl 2-(methoxycarbonylamino)-2-phenylacetateas a white solid (7.7 g). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): 7.98 (d,J=8.0, 1H), 7.37-7.29 (m, 5H), 5.09 (d, J=8, 1H), 3.56 (s, 3H), 1.33 (s,9H). LC (Cond. I): RT=1.53 min; ˜90% homogeneity index; LC/MS: Anal.Calcd. for [M+Na]⁺ C₁₄H₁₉NNaO₄: 288.12; found 288.15.

TFA (16 mL) was added dropwise to a cooled (ice/water) CH₂Cl₂ (160 mL)solution of the above product over 7 minutes, and the cooling bath wasremoved and the reaction mixture was stirred for 20 hours. Since thedeprotection was still not complete, an additional TFA (1.0 mL) wasadded and stirring continued for an additional 2 hours. The volatilecomponent was removed in vacuo, and the resulting oil residue wastreated with diethyl ether (15 mL) and hexanes (12 mL) to provide aprecipitate. The precipitate was filtered and washed with diethylether/hexanes (˜1:3 ratio; 30 mL) and dried in vacuo to provide Cap-4 asa fluffy white solid (5.57 g). Optical rotation: −176.9° [c=3.7 mg/mL inH₂O; λ=589 nm]. ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 12.84 (br s,1H), 7.96 (d, J=8.3, 1H), 7.41-7.29 (m, 5H), 5.14 (d, J=8.3, 1H), 3.55(s, 3H). LC (Cond. I): RT=1.01 min; >95% homogeneity index; LC/MS: Anal.Calcd. for [M+H]⁺ C₁₀N₁₂NO₄ 210.08; found 210.17; HRMS: Anal. Calcd. for[M+H]⁺ C₁₀H₁₂NO₄ 210.0766; found 210.0756.

A mixture of (R)-2-phenylglycine (1.0 g, 6.62 mmol), 1,4-dibromobutane(1.57 g, 7.27 mmol) and Na₂CO₃ (2.10 g, 19.8 mmol) in ethanol (40 mL)was heated at 100° C. for 21 hours. The reaction mixture was cooled toambient temperature and filtered, and the filtrate was concentrated invacuo. The residue was dissolved in ethanol and acidified with 1N HCl topH 3-4, and the volatile component was removed in vacuo. The resultingcrude material was purified by a reverse phase HPLC (water/methanol/TFA)to provide the TFA salt of Cap-5 as a semi-viscous white foam (1.0 g).¹H NMR (DMSO-d₆, δ=2.5, 500 MHz) δ 10.68 (br s, 1H), 7.51 (m, 5H), 5.23(s, 1H), 3.34 (app br s, 2H), 3.05 (app br s, 2H), 1.95 (app br s, 4H);RT=0.30 minutes (Cond. I); >98% homogeneity index; LC/MS: Anal. Calcd.for [M+H]⁺ C₁₂H₁₆NO₂: 206.12; found 206.25.

The TFA salt of Cap-6 was synthesized from (R)-2-phenylglycine and1-bromo-2-(2-bromoethoxy)ethane by using the method of preparation ofCap-5. ¹H NMR (DMSO-d₆, δ=2.5, 500 MHz) δ 12.20 (br s, 1H), 7.50 (m,5H), 4.92 (s, 1H), 3.78 (app br s, 4H), 3.08 (app br s, 2H), 2.81 (appbr s, 2H); RT=0.32 minutes (Cond. I); >98%; LC/MS: Anal. Calcd. for[M+H]⁺ C₁₂H₁₆NO₃: 222.11; found 222.20; HRMS: Anal. Calcd. for [M+H]⁺C₁₂H₁₆NO₃:222.1130; found 222.1121.

A CH₂Cl₂ (200 mL) solution of p-toluenesulfonyl chloride (8.65 g, 45.4mmol) was added dropwise to a cooled (−5° C.) CH₂Cl₂ (200 mL) solutionof (S)-benzyl 2-hydroxy-2-phenylacetate (10.0 g, 41.3 mmol),triethylamine (5.75 mL, 41.3 mmol) and 4-dimethylaminopyridine (0.504 g,4.13 mmol), while maintaining the temperature between −5° C. and 0° C.The reaction was stirred at 0° C. for 9 hours, and then stored in afreezer (−25° C.) for 14 hours. It was allowed to thaw to ambienttemperature and washed with water (200 mL), 1N HCl (100 mL) and brine(100 mL), dried (MgSO₄), filtered, and concentrated in vacuo to providebenzyl 2-phenyl-2-(tosyloxy)acetate as a viscous oil which solidifiedupon standing (16.5 g). The chiral integrity of the product was notchecked and that product was used for the next step without furtherpurification. ¹H NMR (DMSO-d₆, δ=2.5, 500 MHz) δ 7.78 (d, J=8.6, 2H),7.43-7.29 (m, 10H), 7.20 (m, 2H), 6.12 (s, 1H), 5.16 (d, J=12.5, 1H),5.10 (d, J=12.5, 1H), 2.39 (s, 3H). RT=3.00 (Cond. III); >90%homogeneity index; LC/MS: Anal. Calcd. for [M+H]⁺ C₂₂H₂₀NaO₅S: 419.09;found 419.04.

A THF (75 mL) solution of benzyl 2-phenyl-2-(tosyloxy)acetate (6.0 g,15.1 mmol), 1-methylpiperazine (3.36 mL, 30.3 mmol) andN,N-diisopropylethylamine (13.2 mL, 75.8 mmol) was heated at 65° C. for7 hours. The reaction was allowed to cool to ambient temperature and thevolatile component was removed in vacuo. The residue was partitionedbetween ethylacetate and water, and the organic layer was washed withwater and brine, dried (MgSO₄), filtered, and concentrated in vacuo. Theresulting crude material was purified by flash chromatography (silicagel, ethyl acetate) to provide benzyl2-(4-methylpiperazin-1-yl)-2-phenylacetate as an orangish-brown viscousoil (4.56 g). Chiral HPLC analysis (Chiralcel OD-H) indicated that thesample is a mixture of enantiomers in a 38.2 to 58.7 ratio. Theseparation of the enantiomers were effected as follow: the product wasdissolved in 120 mL of ethanol/heptane (1:1) and injected (5mL/injection) on chiral HPLC column (Chiracel OJ, 5 cm ID×50 cm L, 20μm) eluting with 85:15 Heptane/ethanol at 75 mL/min, and monitored at220 nm. Enantiomer-1 (1.474 g) and enantiomer-2 (2.2149 g) wereretrieved as viscous oil. ¹H NMR (CDCl₃, δ=7.26, 500 MHz) 7.44-7.40 (m,2H), 7.33-7.24 (m, 6H), 7.21-7.16 (m, 2H), 5.13 (d, J=12.5, 1H), 5.08(d, J=12.5, 1H), 4.02 (s, 1H), 2.65-2.38 (app br s, 8H), 2.25 (s, 3H).RT=2.10 (Cond. III); >98% homogeneity index; LC/MS: Anal. Calcd. for[M+H]⁺ C₂₀H₂₅N₂O₂: 325.19; found 325.20.

A methanol (10 mL) solution of either enantiomer of benzyl2-(4-methylpiperazin-1-yl)-2-phenylacetate (1.0 g, 3.1 mmol) was addedto a suspension of 10% Pd/C (120 mg) in methanol (5.0 mL). The reactionmixture was exposed to a balloon of hydrogen, under a carefulmonitoring, for <50 minutes. Immediately after the completion of thereaction, the catalyst was filtered through diatomaceous earth (CELITE®)and the filtrate was concentrated in vacuo to provide Cap-7,contaminated with phenylacetic acid as a tan foam (867.6 mg; mass isabove the theoretical yield). The product was used for the next stepwithout further purification. ¹H NMR (DMSO-d₆, δ2.5, 500 MHz) δ7.44-7.37 (m, 2H), 7.37-7.24 (m, 3H), 3.92 (s, 1H), 2.63-2.48 (app. brs, 2H), 2.48-2.32 (m, 6H), 2.19 (s, 3H); RT=0.31 (Cond. II); >90%homogeneity index; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₃H₁₉N₂O₂: 235.14;found 235.15; HRMS: Anal. Calcd. for [M+H]⁺ C₁₃H₁₉N₂O₂: 235.1447; found235.1440.

The synthesis of Cap-8 and Cap-9 was conducted according to thesynthesis of Cap-7 by using appropriate amines for the SN₂ displacementstep (i.e., 4-hydroxypiperidine for Cap-8 and (S)-3-fluoropyrrolidinefor Cap-9) and modified conditions for the separation of the respectivestereoisomeric intermediates, as described below.

The enantiomeric separation of the intermediate benzyl2-(4-hydroxypiperidin-1-yl)-2-phenyl acetate was effected by employingthe following conditions: the compound (500 mg) was dissolved inethanol/heptane (5 mL/45 mL). The resulting solution was injected (5mL/injection) on a chiral HPLC column (Chiracel OJ, 2 cm ID×25 cm L, 10μm) eluting with 80:20 heptane/ethanol at 10 mL/min, monitored at 220nm, to provide 186.3 mg of enantiomer-1 and 209.1 mg of enantiomer-2 aslight-yellow viscous oils. These benzyl ester was hydrogenolysedaccording to the preparation of Cap-7 to provide Cap-8: ¹H NMR (DMSO-d₆, δ=2.5, 500 MHz) 7.40 (d, J=7, 2H), 7.28-7.20 (m, 3H), 3.78 (s 1H),3.46 (m, 1H), 2.93 (m, 1H), 2.62 (m, 1H), 2.20 (m, 2H), 1.70 (m, 2H),1.42 (m, 2H). RT=0.28 (Cond. II); >98% homogeneity index; LC/MS: Anal.Calcd. for [M+H]⁺ C₁₃H₁₈NO₃: 236.13; found 236.07; HRMS: Calcd. for[M+H]⁺ C₁₃H₁₈NO₃: 236.1287; found 236.1283.

The diastereomeric separation of the intermediate benzyl2-((S)-3-fluoropyrrolidin-1-yl)-2-phenylacetate was effected byemploying the following conditions: the ester (220 mg) was separated ona chiral HPLC column (Chiracel OJ-H, 0.46 cm ID×25 cm L, 5 μm) elutingwith 95% CO₂/5% methanol with 0.1% TFA, at 10 bar pressure, 70 mL/minflow rate, and a temperature of 35° C. The HPLC elute for the respectivestereoisomers was concentrated, and the residue was dissolved in CH₂Cl₂(20 mL) and washed with an aqueous medium (10 mL water+1 mL saturatedNaHCO₃ solution). The organic phase was dried (MgSO₄), filtered, andconcentrated in vacuo to provide 92.5 mg of fraction-1 and 59.6 mg offraction-2. These benzyl esters were hydrogenolysed according to thepreparation of Cap-7 to prepare Caps 9a and 9b. Cap-9a (diastereomer-1;the sample is a TFA salt as a result of purification on a reverse phaseHPLC using H₂O/methanol/TFA solvent): ¹H NMR (DMSO-d₆, δ=2.5, 400 MHz)7.55-7.48 (m, 5H), 5.38 (d of m, J=53.7, 1H), 5.09 (br s, 1H), 3.84-2.82(hr m, 4H), 2.31-2.09 (m, 2H). RT=0.42 (Cond. I); >95% homogeneityindex; LC/MS: Anal, Calcd. for [M+H]⁺ C₁₂H₁FNO₂: 224.11; found 224.14;Cap-9b (diastereomer-2): ¹H NMR (DMSO-d₆, δ=2.5, 400 MHz) 7.43-7.21 (m,5H), 5.19 (d of m, J=55.9, 1H), 3.97 (s, 1H), 2.95-2.43 (m, 4H),2.19-1.78 (m, 2H). RT=0.44 (Cond. I); LC/MS: Anal. Calcd. for [M+H]⁺C₁₂H₁₅FNO₂:224.11; found 224.14.

To a solution of D-proline (2.0 g, 17 mmol) and formaldehyde (2.0 mL of37% wt. in H₂O) in methanol (15 mL) was added a suspension of 10% Pd/C(500 mg) in methanol (5 mL). The mixture was stirred under a balloon ofhydrogen for 23 hours. The reaction mixture was filtered throughdiatomaceous earth (CELITE®) and concentrated in vacuo to provide Cap-10as an off-white solid (2.15 g). ¹H NMR (DMSO-d₆, δ=2.5, 500 MHz) 3.42(m, 1H), 3.37 (dd, J=9.4, 6.1, 1H), 2.85-2.78 (m, 1H), 2.66 (s, 3H),2.21-2.13 (m, 1H), 1.93-1.84 (m, 2H), 1.75-1.66 (m, 1H). RT=0.28 (Cond.II); >98% homogeneity index; LC/MS: Anal. Calcd. for [M−H]⁺ C₆H₁₂NO₂:130.09; found 129.96.

A mixture of (2S,4R)-4-fluoropyrrolidine-2-carboxylic acid (0.50 g, 3.8mmol), formaldehyde (0.5 mL of 37% wt. in H₂O), 12 N HCl (0.25 mL) and10% Pd/C (50 mg) in methanol (20 mL) was stirred under a balloon ofhydrogen for 19 hours. The reaction mixture was filtered throughdiatomaceous earth (CELITE®) and the filtrate was concentrated in vacuo.The residue was recrystallized from isopropanol to provide the HCl saltof Cap-11 as a white solid (337.7 mg). ¹H NMR (DMSO-d₆, δ=2.5, 500 MHz)5.39 (d m, J=53.7, 1H), 4.30 (m, 1H), 3.90 (ddd, J=31.5, 13.5, 4.5, 1H),3.33 (dd, J=25.6, 13.4, 1H), 2.85 (s, 3H), 2.60-2.51 (m, 1H), 2.39-2.26(m, 1H). RT=0.28 (Cond. II); >98% homogeneity index; LC/MS: Anal. Calcd.for [M+H]⁺ C₆H, FNO₂: 148.08; found 148.06.

L-Alanine (2.0 g, 22.5 mmol) was dissolved in 10% aqueous sodiumcarbonate solution (50 mL), and a THF (50 mL) solution of methylchloroformate (4.0 mL) was added to it. The reaction mixture was stirredunder ambient conditions for 4.5 hours and concentrated in vacuo. Theresulting white solid was dissolved in water and acidified with 1N HClto a pH 2-3. The resulting solutions was extracted with ethyl acetate(3×100 mL), and the combined organic phase was dried (Na₂SO₄), filtered,and concentrated in vacuo to provide a colorless oil (2.58 g). 500 mg ofthis material was purified by a reverse phase HPLC (H₂O/methanol/TFA) toprovide 150 mg of Cap-12 as a colorless oil. ¹H NMR (DMSO-d₆, δ=2.5, 500MHz) 7.44 (d, J=7.3, 0.8H), 7.10 (br s, 0.2H), 3.97 (m, 1H), 3.53 (s,3H), 1.25 (d, J=7.3, 3H).

A mixture of L-alanine (2.5 g, 28 mmol), formaldehyde (8.4 g, 37 wt. %),1N HCl (30 mL) and 10% Pd/C (500 mg) in methanol (30 mL) was stirredunder a hydrogen atmosphere (50 psi) for 5 hours. The reaction mixturewas filtered through diatomaceous earth (CELITE®) and the filtrate wasconcentrated in vacuo to provide the HCl salt of Cap-13 as an oil whichsolidified upon standing under vacuum (4.4 g; the mass is abovetheoretical yield). The product was used without further purification.¹H NMR (DMSO-d₆, δ=2.5, 500 MHz) δ 12.1 (br s, 1H), 4.06 (q, J=7.4, 1H),2.76 (s, 6H), 1.46 (d, J=7.3, 3H).

Step 1: A mixture of (R)-(−)-D-phenylglycine tert-butyl ester (3.00 g,12.3 mmol), NaBH₃CN (0.773 g, 12.3 mmol), KOH (0.690 g, 12.3 mmol) andacetic acid (0.352 mL, 6.15 mmol) were stirred in methanol at 0° C. Tothis mixture was added glutaric dialdehyde (2.23 mL, 12.3 mmol) dropwiseover 5 minutes. The reaction mixture was stirred as it was allowed towarm to ambient temperature and stirring was continued at the sametemperature for 16 hours. The solvent was subsequently removed and theresidue was partitioned with 10% aqueous NaOH and ethyl acetate. Theorganic phase was separated, dried (MgSO₄), filtered and concentrated todryness to provide a clear oil. This material was purified byreverse-phase preparative HPLC (Primesphere C-18, 30×100 mm;CH₃CN—H₂O—0.1% TFA) to give the intermediate ester (2.70 g, 56%) as aclear oil. ¹H NMR (400 MHz, CDCl₃) δ 7.53-7.44 (m, 3H), 7.40-7.37 (m,2H), 3.87 (d, J=10.9 Hz, 1H), 3.59 (d, J=10.9 Hz, 1H), 2.99 (t, J=11.2Hz, 1H), 2.59 (t, J=11.4 Hz, 1H), 2.07-2.02 (m, 2H), 1.82 (d, J=1.82 Hz,3H), 1.40 (s, 9H). LC/MS: Anal. Calcd. for C₁₇H₂₅NO₂: 275; found: 276(M+H)⁺.

Step 2: To a stirred solution of the intermediate ester (1.12 g, 2.85mmol) in dichloromethane (10 mL) was added TFA (3 mL). The reactionmixture was stirred at ambient temperature for 4 hours and then it wasconcentrated to dryness to give a light yellow oil. The oil was purifiedusing reverse-phase preparative HPLC (Primesphere C-18, 30×100 mm;CH₃CN—H₂O—0.1% TFA). The appropriate fractions were combined andconcentrated to dryness in vacuo. The residue was then dissolved in aminimum amount of methanol and applied to applied to MCX LP extractioncartridges (2×6 g). The cartridges were rinsed with methanol (40 mL) andthen the desired compound was eluted using 2M ammonia in methanol (50mL). Product-containing fractions were combined and concentrated and theresidue was taken up in water. Lyophilization of this solution providedthe title compound (0.492 g, 78%) as a light yellow solid. ¹H NMR(DMSO-d₆) δ7.50 (s, 5H), 5.13 (s, 1H), 3.09 br s, 2H), 2.92-2.89 (m,2H), 1.74 (m, 4H), 1.48 (br s, 2H). LC/MS: Anal. Calcd. for C₁₃H₁₇NO₂:219; found: 220 (M+H)⁺.

Step 1: (S)-1-Phenylethyl 2-bromo-2-phenylacetate: To a mixture ofα-bromophenylacetic acid (10.75 g, 0.050 mol), (S)-(−)-1-phenylethanol(7.94 g, 0.065 mol) and DMAP (0.61 g, 5.0 mmol) in dry dichloromethane(100 mL) was added solid EDCI (12.46 g, 0.065 mol) all at once. Theresulting solution was stirred at room temperature under Ar for 18 hoursand then it was diluted with ethyl acetate, washed (H₂O×2, brine), dried(Na₂SO₄), filtered, and concentrated to give a pale yellow oil. Flashchromatography (SiO₂/hexane-ethyl acetate, 4:1) of this oil provided thetitle compound (11.64 g, 73%) as a white solid. ¹H NMR (400 MHz, CDCl₃)δ 7.53-7.17 (m, 10H), 5.95 (q, J=6.6 Hz, 0.5H), 5.94 (q, J=6.6 Hz,0.5H), 5.41 (s, 0.5H), 5.39 (s, 0.5H), 1.58 (d, J=6.6 Hz, 1.5H), 1.51(d, J=6.6 Hz, 1.5H).

Step 2: (S)-1-Phenylethyl(R)-2-(4-hydroxy-4-methylpiperidin-1-yl)-2-phenylacetate: To a solutionof (S)-1-phenylethyl 2-bromo-2-phenylacetate (0.464 g, 1.45 mmol) in THF(8 mL) was added triethylamine (0.61 mL, 4.35 mmol), followed bytetrabutylammonium iodide (0.215 g, 0.58 mmol). The reaction mixture wasstirred at room temperature for 5 minutes and then a solution of4-methyl-4-hydroxypiperidine (0.251 g, 2.18 mmol) in THF (2 mL) wasadded. The mixture was stirred for 1 hour at room temperature and thenit was heated at 55-60° C. (oil bath temperature) for 4 hours. Thecooled reaction mixture was then diluted with ethyl acetate (30 mL),washed (H₂O×2, brine), dried (MgSO₄), filtered and concentrated. Theresidue was purified by silica gel chromatography (0-60% ethylacetate-hexane) to provide first the (S,R)-isomer of the title compound(0.306 g, 60%) as a white solid and then the corresponding (S,S)-isomer(0.120 g, 23%), also as a white solid. (S,R)-isomer: ¹H NMR (CD₃OD) δ7.51-7.45 (m, 2H), 7.41-7.25 (m, 8H), 5.85 (q, J=6.6 Hz, 1H), 4.05 (s,1H), 2.56-2.45 (m, 2H), 2.41-2.29 (m, 2H), 1.71-1.49 (m, 4H), 1.38 (d,J=6.6 Hz, 3H), 1.18 (s, 3H). LCMS: Anal. Calcd. for C₂₂H₂₇NO₃: 353;found: 354 (M+H)⁺. (S,S)-isomer: ¹H NMR (CD₃OD) δ 7.41-7.30 (m, 5H),7.20-7.14 (m, 3H), 7.06-7.00 (m, 2H), 5.85 (q, J=6.6 Hz, 1H), 4.06 (s,1H), 2.70-2.60 (m, 1H), 2.51 (dt, J=6.6, 3.3 Hz, 1H), 2.44-2.31 (m, 2H),1.75-1.65 (m, 1H), 1.65-1.54 (m, 3H), 1.50 (d, J=6.8 Hz, 3H), 1.20 (s,3H). LCMS: Anal Calcd. for C₂₂H₂₇NO₃: 353; found: 354 (M+H)⁺.

Step 3: (R)-2-(4-Hydroxy-4-methylpiperidin-1-yl)-2-phenylacetic acid: Toa solution of (S)-1-phenylethyl(R)-2-(4-hydroxy-4-methylpiperidin-1-yl)-2-phenylacetate (0.185 g, 0.52mmol) in dichloromethane (3 mL) was added trifluoroacetic acid (1 mL)and the mixture was stirred at room temperature for 2 hours. Thevolatiles were subsequently removed in vacuo and the residue waspurified by reverse-phase preparative HPLC (Primesphere C-18, 20×100 mm;CH₃CN—H₂O—0.1% TFA) to give the title compound (as TFA salt) as a palebluish solid (0.128 g, 98%). LCMS: Anal. Calcd. for C₁₄H₁₉NO₃: 249;found: 250 (M+H)⁺.

Step 1: (S)-1-Phenylethyl 2-(2-fluorophenyl)acetate: A mixture of2-fluorophenylacetic acid (5.45 g, 35.4 mmol), (S)-1-phenylethanol (5.62g, 46.0 mmol), EDCI (8.82 g, 46.0 mmol) and DMAP (0.561 g, 4.60 mmol) inCH₂Cl₂ (100 mL) was stirred at room temperature for 12 hours. Thesolvent was then concentrated and the residue partitioned with H₂O-ethylacetate. The phases were separated and the aqueous layer back-extractedwith ethyl acetate (2×). The combined organic phases were washed (H₂O,brine), dried Na₂SO₄), filtered, and concentrated in vacuo. The residuewas purified by silica gel chromatography (Biotage/0-20% ethylacetate-hexane) to provide the title compound as a colorless oil (8.38g, 92%). ¹H NMR (400 MHz, CD₃OD) δ 7.32-7.23 (m, 7H), 7.10-7.04 (m, 2),5.85 (q, J=6.5 Hz, 1H), 3.71 (s, 2H), 1.48 (d, J=6.5 Hz, 3H).

Step 2: (R)—((S)-1-Phenylethyl)2-(2-fluorophenyl)-2-(piperidin-1-yl)acetate: To a solution of(S)-1-phenylethyl 2-(2-fluorophenyl)acetate (5.00 g, 19.4 mmol) in THF(1200 mL) at 0° C. was added DBU (6.19 g, 40.7 mmol) and the solutionwas allowed to warn to room temperature while stirring for 30 minutes.The solution was then cooled to −78° C. and a solution of CBr₄ (13.5 g,40.7 mmol) in THF (100 mL) was added and the mixture was allowed to warnto −10° C. and stirred at this temperature for 2 hours. The reactionmixture was quenched with saturated aq. NH₄Cl and the layers wereseparated. The aqueous layer was back-extracted with ethyl acetate (2×)and the combined organic phases were washed (H₂O, brine), dried(Na₂SO₄), filtered, and concentrated in vacuo. To the residue was addedpiperidine (5.73 mL, 58.1 mmol) and the solution was stirred at roomtemperature for 24 hours. The volatiles were then concentrated in vacuoand the residue was purified by silica gel chromatography (Biotage/0-30%diethyl ether-hexane) to provide a pure mixture of diastereomers (2:1ratio by ¹H NMR) as a yellow oil (2.07 g, 31%), along with unreactedstarting material (2.53 g, 51%). Further chromatography of thediastereomeric mixture (Biotage/0-10% diethyl ether-toluene) providedthe title compound as a colorless oil (0.737 g, 11%). ¹H NMR (400 MHz,CD₃OD) δ 7.52 (ddd, J=9.4, 7.6, 1.8 Hz, 1H), 7.33-7.40 (m, 1), 7.23-7.23(m, 4H), 7.02-7.23 (m, 4H), 5.86 (q, J=6.6 Hz, 1H), 4.45 (s, 1H),2.39-2.45 (m, 4H), 1.52-1.58 (m, 4H), 1.40-1.42 (m, 1H), 1.38 (d, J=6.6Hz, 3H). LCMS: Anal. Calcd. for C₂₁H₂₄FNO₂: 341; found: 342 (M+H)⁺.

Step 3: (R)-2-(2-fluorophenyl)-2-(piperidin-1-yl)acetic acid: A mixtureof (R)—((S)-1-phenylethyl) 2-(2-fluorophenyl)-2-(piperidin-1-yl)acetate(0.737 g, 2.16 mmol) and 20% Pd(OH)₂/C (0.070 g) in ethanol (30 mL) washydrogenated at room temperature and atmospheric pressure (H₂ balloon)for 2 hours. The solution was then purged with Ar, filtered throughdiatomaceous earth (CELITE®), and concentrated in vacuo. This providedthe title compound as a colorless solid (0.503 g, 98%). ¹H NMR (400 MHz,CD₃OD) δ 7.65 (ddd, J=9.1, 7.6, 1.5 Hz, 1H), 7.47-7.53 (m, 1H),7.21-7.30 (m, 2H), 3.07-3.13 (m, 4H), 1.84 (br s, 4H), 1.62 (br s, 2H).LCMS: Anal. Calcd. for C₁₃H₁₆FNO₂: 237; found: 238 (M+H)⁺.

Step 1: (S)-1-Phenylethyl(R)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-2-phenylacetate: To a solutionof (S)-1-phenylethyl 2-bromo-2-phenylacetate (1.50 g, 4.70 mmol) in THF(25 mL) was added triethylamine (1.31 mL, 9.42 mmol), followed bytetrabutylammonium iodide (0.347 g, 0.94 mmol). The reaction mixture wasstirred at room temperature for 5 minutes and then a solution of4-phenyl-4-hydroxypiperidine (1.00 g, 5.64 mmol) in THF (5 mL) wasadded. The mixture was stirred for 16 hours and then it was diluted withethyl acetate (100 mL), washed (H₂O×2, brine), dried (MgSO₄), filteredand concentrated. The residue was purified on a silica gel column (0-60%ethyl acetate-hexane) to provide an approximately 2:1 mixture ofdiastereomers, as judged by ¹H NMR, Separation of these isomers wasperformed using supercritical fluid chromatography (Chiralcel OJ-H,30×250 mm; 20% ethanol in CO₂ at 35° C.), to give first the (R)-isomerof the title compound (0.534 g, 27%) as a yellow oil and then thecorresponding (S)-isomer (0.271 g, 14%), also as a yellow oil.(S,R)-isomer: ¹H NMR (400 MHz, CD₃OD) δ 7.55-7.47 (m, 4H), 7.44-7.25 (m,10H), 7.25-7.17 (m, 1H), 5.88 (q, J=6.6 Hz, 1H), 4.12 (s, 1H), 2.82-2.72(m, 1H), 2.64 (dt, J=11.1, 2.5 Hz, 1H), 2.58-2.52 (m, 1H), 2.40 (dt,J=1.1, 2.5 Hz, 1H), 2.20 (dt, J=12.1, 4.6 Hz, 1H), 2.10 (dt, J=12.1, 4.6Hz, 1H), 1.72-1.57 (m, 2H), 1.53 (d, J=6.5 Hz, 3H). LCMS: Anal. Calcd.for C₂₇H₂₉NO₃: 415; found: 416 (M+H)⁺; (S,S)-isomer: H¹NMR (400 MHz,CD₃OD) δ 7.55-7.48 (m, 2H), 7.45-7.39 (m, 2H), 7.38-7.30 (m, 5H),7.25-7.13 (m, 4H), 7.08-7.00 (m, 2H), 5.88 (q, J=6.6 Hz, 1H), 4.12 (s,1H), 2.95-2.85 (m, 1H), 2.68 (dt, J=11.1, 2.5 Hz, 1H), 2.57-2.52 (m,1H), 2.42 (dt, J=11.1, 2.5 Hz, 1H), 2.25 (dt, J=2.1, 4.6 Hz, 1H), 2.12(dt, J=12.1, 4.6 Hz, 1H), 1.73 (dd, J=13.6, 3.0 Hz, 1H), 1.64 (dd,J=13.6, 3.0 Hz, 1H), 1.40 (d, J=6.6 Hz, 3H). LCMS: Anal. Calcd. forC₂₇H₂₉NO₃: 415; found: 416 (M+H)⁺.

The following esters were prepared in similar fashion:

Intermediate-17a

Diastereomer 1: ¹H NMR (500 MHz, DMSO-d₆) δ ppm 1.36 (d, J = 6.41 Hz,3H) 2.23-2.51 (m, 4H) 3.35 (s, 4H) 4.25 (s, 1H) 5.05 (s, 2H) 5.82 (d, J= 6.71 Hz, 1H) 7.15-7.52 (m, 15H). LCMS: Anal. Calcd. for: C₂₈H₃₀N₂O₄458.22; Found: 459.44 (M + H)⁺. Diastereomer 2: ¹H NMR (500 MHz,DMSO-d₆) δ ppm 1.45 (d, J = 6.71 Hz, 3H) 2.27-2.44 (m, 4H) 3.39 (s, 4H)4.23 (s, 1H) 5.06 (s, 2H) 5.83 (d, J = 6.71 Hz, 1H) 7.12 (dd, J = 6.41,3.05 Hz, 2H) 7.19-7.27 (m, 3H) 7.27- 7.44 (m, 10H). LCMS: Anal. Calcd.for: C₂₈H₃₀N₂O₄ 458.22; Found: 459.44 (M + H)⁺. Intermediate-17b

Diasteromer 1: RT = 11.76 minutes (Cond'n II); LCMS: Anal. Calcd. for:C₂₀H₂₂N₂O₃ 338.16 Found: 339.39 (M + H)⁺; Diastereomer 2: RT = 10.05minutes (Cond'n II); LCMS: Anal. Calcd. for: C₂₀H₂₂N₂O₃ 338.16; Found:339.39 (M + H)⁺. Intermediate-17c

Diastereomer 1: T_(R) = 4.55 minutes (Cond'n I); LCMS: Anal. Calcd. for:C₂₁H₂₆N₂O₂ 338.20 Found: 339.45 (M + H)⁺; Diastereomer 2: T_(R) = 6.00minutes (Cond'n I); LCMS: Anal. Calcd. for: C₂₁H₂₆N₂O₂ 338.20 Found:339.45 (M + H)⁺. Intermediate-17d

Diastereomer 1: RT = 7.19 minutes (Cond'n I); LCMS: Anal. Calcd. for:C₂₇H₂₉NO₂ 399.22 Found: 400.48 (M + H)⁺; Diastereomer 2: RT = 9.76minutes (Cond'n I); LCMS: Anal. Calcd. for: C₂₇H₂₉NO₂ 399.22 Found:400.48 (M + H)⁺.Chiral SFC Conditions for Determining Retention TimeCondition IColumn: Chiralpak AD-H Column, 4.62×50 mm, 5 μmSolvents: 90% CO₂-10% methanol with 0.1% DEATemp: 35° C.Pressure: 150 barFlow rate: 2.0 mL/min.UV monitored @ 220 nmInjection: 1.0 mg/3 mL methanolCondition IIColumn: Chiralcel OD-H Column, 4.62×50 mm, 5 μmSolvents: 90% CO₂-10% methanol with 0.1% DEATemp: 35° C.Pressure: 150 barFlow rate: 2.0 mL/min.UV monitored @220 nmInjection: 1.0 mg/mL methanol

Cap 17, Step 2; (R)-2-(4-Hydroxy-4-phenylpiperidin-1-yl)-2-phenylaceticacid: To a solution of (S)-1-phenylethyl(R)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-2-phenylacetate (0.350 g, 0.84mmol) in dichloromethane (5 mL) was added trifluoroacetic acid (1 mL)and the mixture was stirred at room temperature for 2 hours. Thevolatiles were subsequently removed in vacuo and the residue waspurified by reverse-phase preparative HPLC (Primesphere C-18, 20×100 mm;CH₃CN—H₂O—0.1% TFA) to give the title compound (as TFA salt) as a whitesolid (0.230 g, 88%). LCMS: Anal. Calcd. for C₁₋₉H₂₁NO₃: 311.15; found:312 (M+H)⁺.

The following carboxylic acids were prepared in optically pure form in asimilar fashion:

Cap-17a

RT = 2.21 (Cond'n II); ¹H NMR (500 MHz, DMSO-d₆) δ ppm 2.20-2.35 (m, 2H)2.34- 2.47 (m, 2H) 3.37 (s, 4H) 3.71 (s, 1H) 5.06 (s, 2H) 7.06-7.53 (m,10H). LCMS: Anal. Calcd. for: C₂₀H₂₂N₂O₄ 354.16; Found: 355.38 (M + H)⁺.Cap-17b

RT = 0.27 (Cond'n III); LCMS: Anal. Calcd. for: C₁₂H₁₄N₂O₃ 234.10;Found: 235.22 (M + H)⁺. Cap-17c

RT = 0.48 (Cond'n II); LCMS: Anal. Calcd. for: C₁₃H₁₈N₂O₂ 234.14; Found:235.31 (M + H)⁺. Cap-17d

RT = 2.21 (Cond'n I); LCMS: Anal. Calcd. for: C₁₉H₂₁NO₂ 295.16; Found:296.33 (M + H)⁺.LCMS Conditions for Determining Retention TimeCondition IColumn: Phenomenex-Luna 4.6×50 mm S10Start % B=0Final % B=100Gradient Time=4 minFlow Rate=4 mL/minWavelength=220Solvent A=10% methanol—90% H₂O—0.1% TFASolvent B=90% methanol—10% H₂O—0.1% TFACondition IIColumn: Waters-Sunfire 4.6×50 mm S5Start % B=0Final % B=100Gradient Time=2 minFlow Rate=4 mL/minWavelength=220Solvent A=10% methanol—90% H₂O—0.1% TFASolvent B=90% methanol—10% H₂O—0.1% TFACondition IIIColumn: Phenomenex 10μ 3.0×50 mmStart % B=0Final % B=100Gradient Time=2 minFlow Rate=4 mL/minWavelength=220Solvent A=10% methanol—90% H₂O—0.1% TFASolvent B=90% methanol—10% H₂O—0.1% TEA

Step 1; (R,S)-Ethyl 2-(4-pyridyl)-2-bromoacetate: To a solution of ethyl4-pyridylacetate (1.00 g, 6.05 mmol) in dry THF (150 mL) at 0° C. underargon was added DBU (0.99 mL, 6.66 mmol). The reaction mixture wasallowed to warm to room temperature over 30 minutes and then it wascooled to −78° C. To this mixture was added CBr₄ (2.21 g, 6.66 mmol) andstirring was continued at −78° C. for 2 hours. The reaction mixture wasthen quenched with sat. aq. NH₄Cl and the phases were separated. Theorganic phase was washed (brine), dried (Na₂SO₄), filtered, andconcentrated in vacuo. The resulting yellow oil was immediately purifiedby flash chromatography (SiO₂/hexane-ethyl acetate, 1:1) to provide thetitle compound (1.40 g, 95%) as a somewhat unstable yellow oil. ¹H NMR(400 MHz, CDCl₃) δ 8.62 (dd, J=4.6, 1.8 Hz, 2H), 7.45 (dd, J=4.6, 1.8Hz, 2H), 5.24 (s, 1H), 4.21-4.29 (m, 2H), 1.28 (t, J=7.1 Hz, 3H). LCMS:Anal. Calcd. for C₉H₁₀BrNO₂: 242, 244; found: 243, 245 (M+H)⁺.

Step 2; (R,S)-Ethyl 2-(4-pyridyl)-2-(N,N-dimethylamino)acetate: To asolution of (R,S)-ethyl 2-(4-pyridyl)-2-bromoacetate (1.40 g, 8.48 mmol)in DMF (10 mL) at room temperature was added dimethylamine (2M in THF,8.5 mL, 17.0 mmol). After completion of the reaction (as judged by thinlayer chromatography) the volatiles were removed in vacuo and theresidue was purified by flash chromatography (Biotage, 40+M SiO₂ column;50%-100% ethyl acetate-hexane) to provide the title compound (0.539 g,31%) as a light yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 8.58 (d, J=6.0 Hz,2H), 7.36 (d, J=6.0 Hz, 2H), 4.17 (m, 2H), 3.92 (s, 1H), 2.27 (s, 6H),1.22 (t, J=7.0 Hz). LCMS: Anal. Calcd. for C₁₁H₁₆N₂O₂: 208; found: 209(M+H)⁺.

Step 3; (R,S)-2-(4-Pyridyl)-2-N,N-dimethylamino)acetic acid: To asolution of (R,S)-ethyl 2-(4-pyridyl)-2-(N,N-dimethylamino)acetate(0.200 g, 0.960 mmol) in a mixture of THF-methanol-H₂O (1:1:1, 6 mL) wasadded powdered LiOH (0.120 g, 4.99 mmol) at room temperature. Thesolution was stirred for 3 hours and then it was acidified to pH 6 using1N HCl. The aqueous phase was washed with ethyl acetate and then it waslyophilized to give the dihydrochloride of the title compound as ayellow solid (containing LiCl). The product was used as such insubsequent steps. ¹H NMR (400 MHz, DMSO-d₆) δ 8.49 (d, J=5.7 Hz, 2H),7.34 (d, J=5.7 Hz, 2H), 3.56 (s, 1H), 2.21 (s, 6H).

The following examples were prepared in similar fashion using the methoddescribed above;

Cap-19

LCMS: Anal. Calcd. for C₉H₁₂N₂O₂: 180; found: 181 (M + H)⁺. Cap-20

LCMS: no ionization. ¹H NMR (400 MHz, CD₃OD) δ 8.55 (d, J = 4.3 Hz, 1H),7.84 (app t, J = 5.3 Hz, 1H), 7.61 (d, J = 7.8 Hz, 1H), 7.37 (app t, J =5.3 Hz, 1H), 4.35 (s, 1H), 2.60 (s, 6H). Cap-21

LCMS: Anal. Calcd. for C₉H₁₁ClN₂O₂: 214, 216; found: 215, 217 (M + H)⁺.Cap-22

LCMS: Anal. Calcd. for C₁₀H₁₂N₂O₄: 224; found: 225 (M + H)⁺. Cap-23

LCMS: Anal. Calcd. for C₁₄H₁₅NO₂: 229; found: 230 (M + H)⁺. Cap-24

LCMS: Anal. Calcd. for C₁₁H₁₂F₃NO₂: 247; found: 248 (M + H)⁺. Cap-25

LCMS: Anal. Calcd. for C₁₁H₁₂F₃NO₂: 247; found: 248 (M + H)⁺. Cap-26

LCMS: Anal. Calcd. for C₁₀H₁₂FNO₂: 197; found: 198 (M + H)⁺. Cap-27

LCMS: Anal. Calcd. for C₁₀H₁₂FNO₂: 247; found: 248 (M + H)⁺. Cap-28

LCMS: Anal. Calcd. for C₁₀H₁₂ClNO₂: 213; found: 214 (M + H)⁺. Cap-29

LCMS: Anal. Calcd. for C₁₀H₁₂ClNO₂: 213; found: 214 (M + H)⁺. Cap-30

LCMS: Anal. Calcd. for C₁₀H₁₂ClNO₂: 213; found: 214 (M + H)⁺. Cap-31

LCMS: Anal. Calcd. for C₈H₁₂N₂O₂S: 200; found: 201 (M + H)⁺. Cap-32

LCMS: Anal. Calcd. for C₈H₁₁NO₂S: 185; found: 186 (M + H)⁺. Cap-33

LCMS: Anal. Calcd. for C₈H₁₁NO₂S: 185; found: 186 (M + H)⁺. Cap-34

LCMS: Anal. Calcd. for C₁₁H₁₂N₂O₃: 220; found: 221 (M + H)⁺. Cap-35

LCMS: Anal. Calcd. for C₁₂H₁₃NO₂S: 235; found: 236 (M + H)⁺. Cap-36

LCMS: Anal. Calcd. for C₁₂H₁₄N₂O₂S: 250; found: 251 (M + H)⁺.

Step 1; (R,S)-Ethyl 2-(quinolin-3-yl)-2-(N,N-dimethylamino)-acetate: Amixture of ethyl N,N-dimethylaminoacetate (0.462 g, 3.54 mmol), K₃PO₄(1.90 g, 8.95 mmol), Pd(t-Bu₃P)₂ (0.090 g, 0.176 mmol) and toluene (10mL) was degassed with a stream of Ar bubbles for 15 minutes. Thereaction mixture was then heated at 100° C. for 12 hours, after which itwas cooled to room temperature and poured into H₂O. The mixture wasextracted with ethyl acetate (2×) and the combined organic phases werewashed (H₂O, brine), dried (Na₂SO₄), filtered, and concentrated invacuo. The residue was purified first by reverse-phase preparative HPLC(Primesphere C-18, 30×100 mm; CH₃CN—H₂O-5 mM NH₄OAc) and then by flashchromatography (SiO₂/hexane-ethyl acetate, 1:1) to provide the titlecompound (0.128 g, 17%) as an orange oil. 1H NMR (400 MHz, CDCl₃) δ 8.90(d, J=2.0 Hz, 1H), 8.32 (d, J=2.0 Hz, 1H), 8.03-8.01 (m, 2H), 7.77 (ddd,J=8.3, 6.8, 1.5 Hz, 1H), 7.62 (ddd, J=8.3, 6.8, 1.5 Hz, 1H), 4.35 (s,1H), 4.13 (m, 2H), 2.22 (s, 6H), 1.15 (t, J=7.0 Hz, 3H). LCMS: Anal.Calcd. for C₁₅H₁₈N₂O₂ 258; found: 259 (M+H)⁺.

Step 2; (R,S) 2-(Quinolin-3-yl)-2-(N,N-dimethylamino)acetic acid: Amixture of (R,S)-ethyl 2-(quinolin-3-yl)-2-N,N-dimethylamino)acetate(0.122 g, 0.472 mmol) and 6M HCl (3 mL) was heated at 100° C. for 12hours. The solvent was removed in vacuo to provide the dihydrochlorideof the title compound (0.169 g, >100%) as a light yellow foam. Theunpurified material was used in subsequent steps without furtherpurification. LCMS: Anal. Calcd. for C₁₃H₁₄N₂O₂: 230; found: 231 (M+H)⁺.

Step 1; (R)—((S)-1-phenylethyl)2-(dimethylamino)-2-(2-fluorophenyl)acetate and (S)—((S)-1-phenylethyl)2-(dimethylamino)-2-(2-fluorophenyl)acetate: To a mixture of(RS)-2-(dimethylamino)-2-(2-fluorophenyl)acetic acid (2.60 g, 13.19mmol), DMAP (0.209 g, 1.71 mmol) and (S)-1-phenylethanol (2.09 g, 17.15mmol) in CH₂Cl₂ (40 mL) was added EDCl (3.29 g, 17.15 mmol) and themixture was allowed to stir at room temperature for 12 hours. Thesolvent was then removed in vacuo and the residue partitioned with ethylacetate-H₂O. The layers were separated, the aqueous layer wasback-extracted with ethyl acetate (2×) and the combined organic phaseswere washed (H₂O, brine), dried (Na₂SO₄), filtered, and concentrated invacuo. The residue was purified by silica gel chromatography(Biotage/0-50% diethyl ether-hexane). The resulting pure diastereomericmixture was then separated by reverse-phase preparative HPLC(Primesphere C-18, 30×100 mm; CH₃CN—H₂O-0.1% TFA) to give first(S)-1-phenethyl (R)-2-(dimethylamino)-2-(2-fluorophenyl)acetate (0.501g, 13%) and then (S)-1-phenethyl(S)-2-(dimethylamino)-2-(2-fluorophenyl)-acetate (0.727 g. 18%), both astheir TFA salts. (S,R)-isomer: ¹H NMR (400 MHz, CD OD) δ 7.65-7.70 (m,1H), 7.55-7.60 (ddd, J=9.4, 8.1, 1.5 Hz, 1H), 7.36-7.41 (m, 2H),7.28-7.34 (m, 5H), 6.04 (q, J=6.5 Hz, 1H), 5.60 (s, 1H), 2.84 (s, 6H),1.43 (d, J=6.5 Hz, 3H). LCMS: Anal. Calcd. for C₁₈H₂₀FNO₂: 301; found:302 (M+H)⁺; (S,S)-isomer. ¹H NMR (400 MHz, CD₃OD) δ 7.58-7.63 (m, 1H),7.18-7.31 (m, 6H), 7.00 (dd, J=8.5, 1.5 Hz, 2H), 6.02 (q, J=6.5 Hz, 1H),5.60 (s, 1H), 2.88 (s, 6H), 1.54 (d, J=6.5 Hz, 3H). LCMS: Anal. Calcd.for C₁₈H₂₀FNO₂ 301; found: 302 (M+H)⁺.

Step 2; (R)-2-(dimethylamino)-2-(2-fluorophenyl)acetic acid: A mixtureof (R)—((S)-1-phenylethyl) 2-(dimethylamino)-2-(2-fluorophenyl)acetateTFA salt (1.25 g, 3.01 mmol) and 20% Pd(OH)₂/C (0.125 g) in ethanol (30mL) was hydrogenated at room temperature and atmospheric pressure (H₂balloon) for 4 hours. The solution was then purged with Ar, filteredthrough diatomaceous earth (CELITE®), and concentrated in vacuo. Thisgave the title compound as a colorless solid (0.503 g, 98%). ¹H NMR (400MHz, CD₃OD) δ 7.53-7.63 (m, 2H), 7.33-7.38 (m, 2H), 5.36 (s, 1H), 2.86(s, 6H). LCMS: Anal. Calcd. for C₁₀H₁₂FNO₂: 197; found: 198 (M+H)⁺.

The S-isomer could be obtained from (S)—((S)-1-phenylethyl)2-(dimethylamino)-2-(2-fluorophenyl)acetate TFA salt in similar fashion.

A mixture of (R)-(2-chlorophenyl)glycine (0.300 g, 1.62 mmol),formaldehyde (35% aqueous solution, 0.80 mL, 3.23 mmol) and 20%Pd(OH)₂/C (0.050 g) was hydrogenated at room temperature and atmosphericpressure (H₂ balloon) for 4 hours. The solution was then purged with Ar,filtered through diatomaceous earth (CELITE®) and concentrated in vacuo.The residue was purified by reverse-phase preparative HPLC (PrimesphereC-18, 30×100 mm; CH₃CN—H₂O-0.1% TFA) to give the TFA salt of the titlecompound (R)-2-(dimethylamino)-2-(2-chlorophenyl)acetic acid as acolorless oil (0.290 g, 55%). ¹H NMR (400 MHz, CD₃OD) δ 7.59-7.65 (m,2H), 7.45-7.53 (m, 2H), 5.40 (s, 1H), 2.87 (s, 6H). LCMS: Anal. Calcd.for C₁₀H₁₂ClNO₂: 213; found: 214 (M+H)⁺.

To an ice-cold solution of (R)-(2-chlorophenyl)glycine (1.00 g, 5.38mmol) and NaOH (0.862 g, 21.6 mmol) in H₂O (5.5 mL) was added methylchloroformate (1.00 mL, 13.5 mmol) dropwise. The mixture was allowed tostir at 0° C. for 1 hour and then it was acidified by the addition ofconc. HCl (2.5 mL). The mixture was extracted with ethyl acetate (2×)and the combined organic phase was washed (H₂O, brine), dried (Na₂SO₄),filtered, and concentrated in vacuo to give the title compound(R)-2-(methoxycarbonylamino)-2-(2-chlorophenyl)acetic acid as ayellow-orange foam (1.31 g, 96%). ¹H NMR (400 MHz, CD₃OD) δ 7.39-7.43(m, 2H), 7.29-7.31 (m, 2H), 5.69 (s, 1H), 3.65 (s, 3H). LCMS; Anal.Calcd. for C₁₁H₁₀ClNO₄: 243; found: 244 (M+H)⁺.

To a suspension of 2-(2-(chloromethyl)phenyl)acetic acid (2.00 g, 10.8mmol) in THF (20 mL) was added morpholine (1.89 g, 21.7 mmol) and thesolution was stirred at room temperature for 3 hours. The reactionmixture was then diluted with ethyl acetate and extracted with H₂O (2×).The aqueous phase was lyophilized and the residue was purified by silicagel chromatography (Biotage/0-10% methanol-CH₂Cl₂) to give the titlecompound 2-(2-(Morpholinomethyl)phenyl)acetic acid as a colorless solid(2.22 g, 87%). ¹H NMR (400 MHz, CD₃OD) δ 7.37-7.44 (m, 3H), 7.29-7.33(m, 1H), 4.24 (s, 2H), 3.83 (br s, 4H), 3.68 (s, 2H), 3.14 (br s, 4H).LCMS: Anal. Calcd. for C₁₃H₁₇NO₃; 235; found: 236 (M+H)⁺.

The following examples were similarly prepared using the methoddescribed for Cap-41:

Cap-42

LCMS: Anal. Calcd. for C₁₄H₁₉NO₂: 233; found: 234 (M + H)⁺. Cap-43

LCMS: Anal. Calcd. for C₁₃H₁₇NO₂: 219; found: 220 (M + H)⁺. Cap-44

LCMS: Anal. Calcd. for C₁₁H₁₅NO₂: 193; found: 194 (M + H)⁺. Cap-45

LCMS: Anal. Calcd. for C₁₄H₂₀N₂O₂: 248; found: 249 (M + H)⁺.

HMDS (1.85 mL, 8.77 mmol) was added to a suspension of(R)-2-amino-2-phenylacetic acid p-toluenesulfonate (2.83 g, 8.77 mmol)in CH₂Cl₂ (10 mL) and the mixture was stirred at room temperature for 30minutes. Methyl isocyanate (0.5 g, 8.77 mmol) was added in one portionstirring continued for 30 minutes. The reaction was quenched by additionof H₂O (5 mL) and the resulting precipitate was filtered, washed withH₂O and n-hexanes, and dried under vacuum.(R)-2-(3-methylureido)-2-phenylacetic acid (1.5 g; 82%) was recovered asa white solid and it was used without her purification. ¹H NMR (500 MHz,DMSO-d₆) δ ppm 2.54 (d, J=4.88 Hz, 3H) 5.17 (d, J=7.93 Hz, 1H) 5.95 (q,J=4.48 Hz, 1H) 6.66 (d, J=7.93 Hz, 1H)

7.26-7.38 (m, 5H) 12.67 (s, 1H). LCMS: Anal. Calcd. for C₁₀H₁₂N₂O₃208.08 found 209.121 (M+H)⁺; HPLC Phenomenex C-18 3.0×46 mm, 0 to 100% Bover 2 minutes, 1 minute hold time, A=90% water, 10% methanol, 0.1% TFA,B=10% water, 90% methanol, 0.1% TFA, RT=1.38 min, 90% homogeneity index.

The desired product was prepared according to the method described forCap-45a. ¹H NMR (500 MHz, DMSO-d₆) δ ppm 0.96 (t, J=7.17 Hz, 3H)2.94-3.05 (m, 2H) 5.17 (d, J=7.93 Hz, 1H) 6.05 (t, J=5.19 Hz, 1H) 6.60(d, J=7.63 Hz, 1H) 7.26-7.38 (m, 5H) 12.68 (s, 1H). LCMS: Anal. Calcd.for C₁₁H₁₄N₂O₃ 222.10 found 223.15 (M+H)⁺. HPLC XTERRA C-18 3.0×506 mm,0 to 100% B over 2 minutes, 1 minute hold time, A=90% water, 10%methanol, 0.2% H₃PO₄, B=10% water, 90% methanol, 0.2% H₃PO₄, RT=0.87min, 90% homogeneity index.

Step 1; (R)-tert-butyl 2-(3,3-dimethylureido)-2-phenylacetate: To astirred solution of (R)-tert-butyl-2-amino-2-phenylacetate (1.0 g, 4.10mmol) and Hunig's base (1.79 mL, 10.25 mmol) in DMF (40 mL) was addeddimethylcarbamoyl chloride (0.38 mL, 4.18 mmol) dropwise over 10minutes. After stirring at room temperature for 3 hours, the reactionwas concentrated under reduced pressure and the resulting residue wasdissolved in ethyl acetate. The organic layer was washed with H₂O, 1Naq. HCl and brine, dried (MgSO₄), filtered and concentrated underreduced pressure. (R)-tert-butyl 2-(3,3-dimethylureido)-2-phenylacetatewas obtained as a white solid (0.86 g; 75%) and used without furtherpurification. ¹H NMR (500 MHz, DMSO-d₆) δ ppm 1.33 (s, 9H) 2.82 (s, 6H)5.17 (d, J=7.63 Hz, 1H) 6.55 (d, J=7.32 Hz, 1H) 7.24-7.41 (m, 5H). LCMS:Anal. Calcd. for C₁₅H₂₂N₂O₃ 278.16 found 279.23 (M+H)⁺; HPLC PhenomenexLUNA C-18 4.6×50 mm, 0 to 100% B over 4 minutes, 1 minute hold time,A=90% water, 10% methanol, 0.1% TFA, B=10% water, 90% methanol, 0.1%TFA, RT=2.26 min, 97% homogeneity index.

Step 2; (R)-2-(3,3-dimethylureido)-2-phenylacetic acid: To a stirredsolution of ((R)-tert-butyl 2-(3,3-dimethylureido)-2-phenylacetate (0.86g, 3.10 mmol) in CH₂Cl₂ (250 mL) was added TFA (15 mL) dropwise and theresulting solution was stirred at rt for 3 hours. The desired compoundwas then precipitated out of solution with a mixture of EtOAC:Hexanes(5:20), filtered off and dried under reduced pressure.(R)-2-(3,3-dimethylureido)-2-phenylacetic acid was isolated as a whitesolid (0.59 g, 86%) and used without further purification. ¹H NMR (500MHz, DMSO-d₆) δ ppm 2.82 (s, 6H) 5.22 (d, J=7.32 Hz, 1H) 6.58 (d, J=7.32Hz, 1H) 7.28 (t, J=7.17 Hz, 1H) 7.33 (t, J=7.32 Hz, 2H) 7.38-7.43 (m,2H) 12.65 (s, 1H). LCMS; Anal. Calcd. for C₁₁H₁₄N₂O₃: 222.24; found:223.21 (M+H)⁺. HPLC XTERRA C-18 3.0×50 mm, 0 to 100% B over 2 minutes, 1minute hold time, A=90% water, 10% methanol, 0.2% H₃PO₄, B=10% water,90% methanol, 0.2% H₃PO₄, RT=0.75 min, 93% homogeneity index.

Step 1; (R)-tert-butyl 2-(3-cyclopentylureido)-2-phenylacetate: To astirred solution of (R)-2-amino-2-phenylacetic acid hydrochloride (1.0g, 4.10 mmol) and Hunig's base (1.0 mL, 6.15 mmol) in DMF (15 mL) wasadded cyclopentyl isocyanate (0.46 mL, 4.10 mmol) dropwise and over 10minutes. After stirring at room temperature for 3 hours, the reactionwas concentrated under reduced pressure and the resulting residue wastaken up in ethyl acetate. The organic layer was washed with H₂O andbrine, dried (MgSO₄), filtered, and concentrated under reduced pressure.(R)-tert-butyl 2-(3-cyclopentylureido)-2-phenylacetate was obtained asan opaque oil (1.32 g; 100%) and used without further purification. ¹HNMR (500 MHz, CD₃Cl-D) δ ppm 1.50-1.57 (m, 2H) 1.58-1.66 (m, 2H)1.87-1.97 (m, 2H) 3.89-3.98 (m, 1H) 5.37 (s, 1H) 7.26-7.38 (m, 5H).LCMS: Anal. Calcd. for C₁₈H₂₆N₂O₃ 318.19 found 319.21 (M+H)⁺; HPLCXTERRA C-18 3.0×50 mm, 0 to 100% B over 4 minutes, 1 minute hold time,A=90% water, 10% methanol, 0.1% TFA, B=10% water, 90% methanol, 0.1%TFA, RT=2.82 min, 96% homogeneity index.

Step 2; (R)-2-(3-cyclopentylureido)-2-phenylacetic acid: To a stirredsolution of (R)-tert-butyl 2-(3-cyclopentylureido)-2-phenylacetate (1.31g, 4.10 mmol) in CH₂Cl₂ (25 mL) was added TFA (4 mL) and trietheylsilane(1.64 mL; 10.3 mmol) dropwise, and the resulting solution was stirred atroom temperature for 6 hours. The volatile components were removed underreduced pressure and the crude product was recrystallized in ethylacetate/pentanes to yield (R)-2-(3-cyclopentylureido)-2-phenylaceticacid as a white solid (0.69 g, 64%). ¹H NMR (500 MHz, DMSO-d₆) δ ppm1.17-1.35 (m, 2H) 1.42-1.52 (m, 2H) 1.53-1.64 (m, 2H) 1.67-1.80 (m, 2H)3.75-3.89 (m, 1H) 5.17 (d, J=7.93 Hz, 1H) 6.12 (d, J=7.32 Hz, 1H) 6.48(d, J=7.93 Hz, 1H) 7.24-7.40 (m, 5H) 12.73 (s, 1H). LCMS: Anal. Calcd.for C₁₄H₁₈N₂O₃: 262.31; found: 263.15 (M+H)⁺. HPLC XTERRA C-18 3.0×50mm, 0 to 100% B over 2 minutes, 1 minute hold time, A=90% water, 10%methanol, 0.2% H₃PO₄, B=10% water, 90% methanol, 0.2% H₃PO₄, RT=1.24min, 100% homogeneity index.

To a stirred solution of 2-(benzylamino)acetic acid (2.0 g, 12.1 mmol)in formic acid (91 mL) was added formaldehyde (6.94 mL, 93.2 mmol).After five hours at 70° C., the reaction mixture was concentrated underreduced pressure to 20 mL and a white solid precipitated. Followingfiltration, the mother liquors were collected and further concentratedunder reduced pressure providing the crude product. Purification byreverse-phase preparative HPLC (Xterra 30×100 mm, detection at 220 nm,flow rate 35 mL/min, 0 to 35% B over 8 min; A=90% water, 10% methanol,0.1% TFA, B=10% water, 90% methanol, 0.1% TFA) provided the titlecompound 2-(benzyl(methyl)-amino)acetic acid as its TFA salt (723 mg,33%) as a colorless wax. ¹H NMR (300 MHz, DMSO-d₆) δ ppm 2.75 (s, 3H)4.04 (s, 2H) 4.34 (s, 2H) 7.29-7.68 (m, 5H). LCMS: Anal. Calcd. for:C₁₀H₁₃NO₂ 179.09; Found: 180.20 (M+H)⁺.

To a stirred solution of 3-methyl-2-(methylamino)butanoic acid (0.50 g,3.81 mmol) in water (30 mL) was added K₂CO₃ (2.63 g, 19.1 mmol) andbenzyl chloride (1.32 g, 11.4 mmol). The reaction mixture was stirred atambient temperature for 18 hours. The reaction mixture was extractedwith ethyl acetate (30 mL×2) and the aqueous layer was concentratedunder reduced pressure providing the crude product which was purified byreverse-phase preparative HPLC (Xterra 30×100 mm, detection at 220 mm,flow rate 40 mL/min, 20 to 80% B over 6 mm; A=90% water, 10% methanol,0.1% TFA, B=10% water, 90% methanol, 0.1% TFA) to provide2-(benzyl(methyl)amino)-3-methylbutanoic acid, TFA salt (126 mg, 19%) asa colorless wax. ¹H NMR (500 MHz, DMSO-d₆) δ ppm 0.98 (d, 3H) 1.07 (d,3H) 2.33-2.48 (m, 1H) 2.54-2.78 (m, 3H) 3.69 (s, 1H) 4.24 (s, 2H)7.29-7.65 (m, 5H). LCMS: Anal. Calcd. for: C₁₃H₁₉NO₂ 221.14; Found:222.28 (M+H)⁺.

Na₂CO₃ (1.83 g, 17.2 mmol) was added to NaOH (33 mL of 1M/H₂O, 33 mmol)solution of L-valine (3.9 g, 33.29 mmol) and the resulting solution wascooled with ice-water bath. Methyl chloroformate (2.8 mL, 36.1 mmol) wasadded dropwise over 15 min, the cooling bath was removed and thereaction mixture was stirred at ambient temperature for 3.25 hr. Thereaction mixture was washed with ether (50 mL, 3×), and the aqueousphase was cooled with ice-water bath and acidified with concentrated HClto a pH region of 1-2, and extracted with CH₂Cl₂ (50 mL, 3×). Theorganic phase was dried (MgSO₄) and evaporated in vacuo to afford Cap-51as a white solid (6 g). ¹H NMR for the dominant rotamer (DMSO-d₆, δ=2.5ppm, 500 MHz): 12.54 (s, 1H), 7.33 (d, J=8.6, 1H), 3.84 (dd, J=8.4, 6.0,1H), 3.54 (s, 3H), 2.03 (m, 1H), 0.87 (m, 6H). HRMS: Anal. Calcd. for[M+H]⁺ C₇H₁₄NO₄: 176.0923; found 176.0922.

Cap-52 was synthesized from L-alanine according to the proceduredescribed for the synthesis of Cap-51. For characterization purposes, aportion of the crude material was purified by a reverse phase HPLC(H₂O/methanol/TFA) to afford Cap-52 as a colorless viscous oil. ¹H NMR(DMSO-d₆, δ=2.5 ppm, 500 MHz): 12.49 (br s, 1H), 7.43 (d, J=7.3, 0.88H),7.09 (app br s, 0.12H), 3.97 (m, 1H), 3.53 (s, 3H), 1.25 (d, J=7.3, 3H).

Cap-53 to −64 were prepared from appropriate starting materialsaccording to the procedure described for the synthesis of Cap-51, withnoted modifications if any,

Cap Structure Data Cap-53a: (R) Cap-53b: (S)

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ12.51 (br s, 1H), 7.4 (d, J =7.9, 0.9H), 7.06 (app s, 0.1H), 3.86-3.82 (m, 1H), 3.53 (s, 3H),1.75-1.67 (m, 1H), 1.62-1.54 (m, 1H), 0.88 (d, J = 7.3, 3H). RT = 0.77minutes (Cond. 2); LC/MS: Anal. Calcd. for [M + Na]⁺ C₆H₁₁NNaO₄: 184.06;found 184.07. HRMS Calcd. for [M + Na]⁺ C₆H₁₁NNaO₄: 184.0586; found184.0592. Cap-54a: (R) Cap-54b: (S)

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 12.48 (s, 1H), 7.58 (d, J =7.6, 0.9H), 7.25 (app s, 0.1H), 3.52 (s, 3H), 3.36-3.33 (m, 1H),1.10-1.01 (m, 1H), 0.54-0.49 (m, 1H), 0.46-0.40 (m, 1H), 0.39-0.35 (m,1H), 0.31-0.21 (m, 1H). HRMS Calcd. for [M + H]⁺ C₇H₁₂NO₄: 174.0766;found 174.0771 Cap-55

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 12.62 (s, 1H), 7.42 (d, J =8.2, 0.9H), 7.07 (app s, 0.1H), 5.80-5.72 (m, 1H), 5.10 (d, J = 17.1,1H), 5.04 (d, J = 10.4, 1H), 4.01-3.96 (m, 1H), 3.53 (s, 3H), 2.47-2.42(m, 1H), 2.35-2.29 (m, 1H). Cap-56

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 12.75 (s, 1H), 7.38 (d, J =8.3, 0.9H), 6.96 (app s, 0.1H), 4.20-4.16 (m, 1H), 3.60-3.55 (m, 2H),3.54 (s, 3H), 3.24 (s, 3H). Cap-57

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 12.50 (s, 1H), 8.02 (d, J =7.7, 0.08H), 7.40 (d, J = 7.9, 0.76H), 7.19 (d, J = 8.2, 0.07H), 7.07(d, J = 6.7, 0.09H), 4.21-4.12 (m, 0.08H), 4.06-3.97 (m, 0.07H),3.96-3.80 (m, 0.85H), 3.53 (s, 3H), 1.69-1.51 (m, 2H), 1.39-1.26 (m,2H), 0.85 (t, J = 7.4, 3H). LC (Cond. 2): RT = 1.39 LC/MS: Anal. Calcd.for [M + H]⁺ C₇H₁₄NO₄: 176.09; found 176.06. Cap-58

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 12.63 (br s, 1H), 7.35 (s,1H), 7.31 (d, J = 8.2, 1H), 6.92 (s, 1H), 4.33-4.29 (m, 1H), 3.54 (s,3H), 2.54 (dd, J = 15.5, 5.4, 1H), 2.43 (dd, J = 15.6, 8.0, 1H). RT =0.16 min (Cond. 2); LC/MS: Anal. Calcd. for [M + H]⁺ C₆H₁₁N₂O₅: 191.07;found 191.14. Cap-59a: (R) Cap-59b: (S)

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz): δ 12.49 (br s, 1H), 7.40 (d, J =7.3, 0.89H), 7.04 (br s, 0.11H), 4.00-3.95 (m, 3H), 1.24 (d, J = 7.3,3H), 1.15 (t, J = 7.2, 3H). HRMS: Anal. Calcd. for [M + H]⁺ C₆H₁₂NO₄:162.0766; found 162.0771. Cap-60

The crude material was purified with a reverse phase HPLC (H₂O/MeOH/TFA)to afford a colorless viscous oil that crystallized to a white solidupon exposure to high vacuum. ¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz): δ12.38 (br s, 1H), 7.74 (s, 0.82H), 7.48 (s, 0.18H), 3.54/3.51 (two s,3H), 1.30 (m, 2H), 0.98 (m, 2H). HRMS: Anal. Calcd. for [M + H]⁺C₆H₁₀NO₄: 160.0610; found 160.0604. Cap-61

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz): δ 12.27 (br s, 1H), 7.40 (br s,1H), 3.50 (s, 3H), 1.32 (s, 6H). HRMS: Anal. Calcd. for [M + H]⁺C₆H₁₂NO₄: 162.0766; found 162.0765. Cap-62

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz): δ 12.74 (br s, 1H), 4.21 (d, J =10.3, 0.6H), 4.05 (d, J = 10.0, 0.4H), 3.62/3.60 (two singlets, 3H), 3.0(s, 3H), 2.14-2.05 (m, 1H), 0.95 (d, J = 6.3, 3H), 0.81 (d, J = 6.6,3H). LC/MS: Anal. Calcd. for [M − H]⁻ C₈H₁₄NO₄: 188.09; found 188.05.Cap-63

[Note: the reaction was allowed to run for longer than what was notedfor the general procedure.] ¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz):12.21 (br s, 1H), 7.42 (br s, 1H), 3.50 (s, 3H), 2.02-1.85 (m, 4H),1.66-1.58 (m, 4H). LC/MS: Anal. Calcd. for [M + H]⁺ C₈H₁₄NO₄: 188.09;found 188.19. Cap-64

[Note: the reaction was allowed to run for longer than what was notedfor the general procedure.] ¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz):12.35 (br s, 1H), 7.77 (s, 0.82H), 7.56/7.52 (overlapping br s, 0.18H),3.50 (s, 3H), 2.47-2.40 (m, 2H), 2.14-2.07 (m, 2H), 1.93-1.82 (m, 2H).

Methyl chloroformate (0.65 mL, 8.39 mmol) was added dropwise over 5 minto a cooled (ice-water) mixture of Na₂CO₃ (0.449 g, 4.23 mmol), NaOH(8.2 mL of 1M/H₂O, 8.2 mmol) and (S)-2-amino-3-hydroxy-3-methylbutanoicacid (1.04 g, 7.81 mmol). The reaction mixture was stirred for 45 min,and then the cooling bath was removed and stirring was continued for anadditional 3.75 hr. The reaction mixture was washed with CH₂Cl₂, and theaqueous phase was cooled with ice-water bath and acidified withconcentrated HCl to a pH region of 1-2. The volatile component wasremoved in vacuo and the residue was taken up in a 2:1 mixture ofMeOH/CH₂Cl₂ (15 mL) and filtered, and the filterate was rotervaped toafford Cap-65 as a white semi-viscous foam (1.236 g). ¹H NMR (DMSO-d₆,δ=2.5 ppm, 400 MHz): δ 6.94 (d, J=8.5, 0.9H), 6.53 (br s, 0.1H), 3.89(d, J=8.8, 1H), 2.94 (s, 3H), 1.15 (s, 3H), 1.13 (s, 3H).

Cap-66 and -67 were prepared from appropriate commercially availablestarting materials by employing the procedure described for thesynthesis of Cap-65.

¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 12.58 (br s, 1H), 7.07 (d,J=8.3, 0.13H), 6.81 (d, J=8.8, 0.67H), 4.10-4.02 (m, 1.15H), 3.91 (dd,J=9.1, 3.5, 0.85H), 3.56 (s, 3H), 1.09 (d, J=6.2, 3H). [Note: only thedominant signals of NH were noted].

¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): 12.51 (br s, 1H), 7.25 (d, J=8.4,0.75H), 7.12 (br d, J=0.4, 0.05H), 6.86 (br s, 0.08H), 3.95-3.85 (m,2H), 3.54 (s, 3H), 1.08 (d, J=6.3, 3H). [Note: only the dominant signalsof NH were noted].

Methyl chloroformate (0.38 ml, 4.9 mmol) was added drop-wise to amixture of 1N NaOH (aq) (9.0 ml, 9.0 mmol), 1M NaHCO₃ (aq) (9.0 ml, 9.0mol), L-aspartic acid β-benzyl ester (1.0 g, 4.5 mmol) and Dioxane (9ml). The reaction mixture was stirred at ambient conditions for 3 hr,and then washed with Ethyl acetate (50 ml, 3×). The aqueous layer wasacidified with 12N HCl to a pH 1-2, and extracted with ethyl acetate(3×50 ml). The combined organic layers were washed with brine, dried(Na₂SO₄), filtered, and concentrated in vacuo to afford Cap-68 as alight yellow oil (1.37 g; mass is above theoretical yield, and theproduct was used without further purification). ¹H NMR (DMSO-d₆, δ=2.5ppm, 500 MHz): δ 12.88 (br s, 1H), 7.55 (d, J=8.5, 1H), 7.40-7.32 (m,5H), 5.13 (d, J=12.8, 1H), 5.10 (d, J=12.9, 1H), 4.42-4.38 (m, 1H), 3.55(s, 3H), 2.87 (dd, J=16.2, 5.5, 1H), 2.71 (dd, J=16.2, 8.3, 1H). LC(Cond. 2): RT=1.90 min; LC/MS: Anal. Calcd. For [M+H]⁺ C₁₃H₁₆NO₆:282.10; found 282.12.

NaCNBH₃ (2.416 g, 36.5 mmol) was added in batches to a chilled (˜15° C.)water (17 mL)/MeOH (10 mL) solution of alanine (1.338 g, 15.0 mmol). Afew minutes later acetaldehyde (4.0 mL, 71.3 mmol) was added drop-wiseover 4 min, the cooling bath was removed, and the reaction mixture wasstirred at ambient condition for 6 hr. An additional acetaldehyde (4.0mL) was added and the reaction was stirred for 2 hr. Concentrated HClwas added slowly to the reaction mixture until the pH reached ˜1.5, andthe resulting mixture was heated for 1 hr at 40° C. Most of the volatilecomponent was removed in vacuo and the residue was purified with aDOWEX® 50WX8-100 ion-exchange resin (column was washed with water, andthe compound was eluted with dilute NH₄OH, prepared by mixing 18 ml ofNH₄OH and 282 ml of water) to afford Cap-69 (2.0 g) as an off-white softhygroscopic solid, ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 3.44 (q,J=7.1, 1H), 2.99-2.90 (m, 2H), 2.89-2.80 (m, 2H), 1.23 (d, J=7.1, 3H),1.13 (t, J=7.3, 6H).

Cap-70 to −74× were prepared according to the procedure described forthe synthesis of Cap-69 by employing appropriate starting materials.

Cap-70a: (R) Cap-70b: (S)

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz): δ 3.42 (q, J = 7.1, 1H),2.68-2.60 (m, 4H), 1.53-1.44 (m, 4H), 1.19 (d, J = 7.3, 3H), 0.85 (t, J= 7.5, 6H). LC/MS: Anal. Calcd. for [M + H]⁺ C₉H₂₀NO₂: 174.15; found174.13. Cap-71a: (R) Cap-71b: (S)

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 3.18-3.14 (m, 1H), 2.84-2.77(m, 2H), 2.76-2.68 (m, 2H), 1.69-1.54 (m, 2H), 1.05 (t, J = 7.2, 6H),0.91 (t, J = 7.3, 3H). LC/MS: Anal. Calcd. for [M + H]⁺ C₈H₁₈NO₂:160.13; found 160.06. Cap-72

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 400 MHz): δ 2.77-2.66 (m, 3H), 2.39-2.31(m, 2H), 1.94-1.85 (m, 1H), 0.98 (t, J = 7.1, 6H), 0.91 (d, J = 6.5,3H), 0.85 (d, J = 6.5 , 3H). LC/MS: Anal. Calcd. for [M + H]⁺ C₉H₂₀NO₂:174.15; found 174.15. Cap-73

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 9.5 (br s, 1H), 3.77 (dd, J =10.8, 4.1, 1H), 3.69-3.61 (m, 2H), 3.26 (s, 3H), 2.99-2.88 (m, 4H), 1.13(t, J = 7.2, 6H). Cap-74

¹H NMR (DMSO-d₆, δ = 2.5 ppm, 500 MHz): δ 7.54 (s, 1H), 6.89 (s, 1H),3.81 (t, J = 6.6, k, 1H), 2.82-2.71 (m, 4H), 2.63 (dd, J = 15.6, 7.0,1H), 2.36 (dd, J = 15.4, 6.3, 1H), 1.09 (t, J = 7.2, 6H). RT = 0.125minutes (Cond. 2); LC/MS: Anal. Calcd. for [M + H]⁺ C₈H₁₇N₂O₃: 189.12;found 189.13. Cap-74x

LC/MS: Anal. Calcd. for [M + H]⁺ C₁₀H₂₂NO₂: 188.17; found 188.21

NaBH₃CN (1.6 g, 25.5 mmol) was added to a cooled (ice/water bath) water(25 ml)/methanol (15 ml) solution of H-D-Ser-OBzl HCl (2.0 g, 8.6 mmol).Acetaldehyde (1.5 ml, 12.5 mmol) was added drop-wise over 5 min, thecooling bath was removed, and the reaction mixture was stirred atambient condition for 2 hr. The reaction was carefully quenched with12NHCl and concentrated in vacuo. The residue was dissolved in water andpurified with a reverse phase HPLC (MeOH/H₂O/TFA) to afford the TFA saltof (R)-benzyl 2-(diethylamino)-3-hydroxypropanoate as a colorlessviscous oil (1.9 g). 1H NMR (DMSO-d₆, δ=2.5 ppm, 500 MHz): δ 9.73 (br s,1H), 7.52-7.36 (m, 5H), 5.32 (d, J=12.2, 1H), 5.27 (d, J=12.5, 1H),4.54-4.32 (m, 1H), 4.05-3.97 (m, 2H), 3.43-3.21 (m, 4H), 1.23 (t, J=7.2,6H). LC/MS (Cond. 2): RT=1.38 min; LC/MS: Anal. Calcd. for [M+H]⁺C₁₄H₂₂NO₃: 252.16; found 252.19.

Cap-75

NaH (0.0727 g, 1.82 mmol, 60%) was added to a cooled (ice-water) THF(3.0 mL) solution of the TFA salt (R)-benzyl2-(diethylamino)-3-hydroxypropanoate (0.3019 g, 0.8264 mmol) preparedabove, and the mixture was stirred for 15 min. Methyl iodide (56 μL,0.90 mmol) was added and stirring was continued for 18 hr while allowingthe bath to thaw to ambient condition. The reaction was quenched withwater and loaded onto a MeOH pre-conditioned MCX (6 g) cartridge, andwashed with methanol followed by compound elution with 2N NH₃/Methanol.Removal of the volatile component in vacuo afforded Cap-75, contaminatedwith (R)-2-(diethylamino)-3-hydroxypropanoic acid, as a yellowsemi-solid (100 mg). The product was used as is without furtherpurification.

NaCNBH₃ (1.60 g, 24.2 mmol) was added in batches to a chilled (˜15° C.)water/MeOH (12 mL each) solution of(S)-4-amino-2-(tert-butoxycarbonylamino) butanoic acid (2.17 g, 9.94mmol). A few minutes later acetaldehyde (2.7 mL, 48.1 mmol) was addeddrop-wise over 2 min, the cooling bath was removed, and the reactionmixture was stirred at ambient condition for 3.5 hr. An additionalacetaldehyde (2.7 mL, 48.1 mmol) was added and the reaction was stirredfor 20.5 hr. Most of the MeOH component was removed in vacuo, and theremaining mixture was treated with concentrated HCl until its pH reached˜1.0 and then heated for 2 hr at 40° C. The volatile component wasremoved in vacuo, and the residue was treated with 4 M HCl/dioxane (20mL) and stirred at ambient condition for 7.5 hr. The volatile componentwas removed in vacuo and the residue was purified with DOWEX® 50WX8-100ion-exchange resin (column was washed with water and the compound waseluted with dilute NH₄OH, prepared from 18 ml of NH₄OH and 282 ml ofwater) to afford intermediate (S)-2-amino-4-(diethylamino)butanoic acidas an off-white solid (1.73 g).

Methyl chloroformate (0.36 mL, 4.65 mmol) was added drop-wise over 11min to a cooled (ice-water) mixture of Na₂CO₃ (0.243 g, 2.29 mmol), NaOH(4.6 mL of 1M/H₂O, 4.6 mmol) and the above product (802.4 mg). Thereaction mixture was stirred for 55 min, and then the cooling bath wasremoved and stirring was continued for an additional 5.25 hr. Thereaction mixture was diluted with equal volume of water and washed withCH₂Cl₂ (30 mL, 2×), and the aqueous phase was cooled with ice-water bathand acidified with concentrated HCl to a pH region of 2. The volatilecomponent was then removed in vacuo and the crude material wasfree-based with MCX resin (6.0 g; column was washed with water, andsample was eluted with 2.0 M NH₃/MeOH) to afford impure Cap-76 as anoff-white solid (704 mg). ¹H NMR (MeOH-d₄, δ=3.29 ppm, 400 MHz): δ 3.99(dd, J=7.5, 4.7, 1H), 3.62 (s, 3H), 3.25-3.06 (m, 6H), 2.18-2.09 (m,1H), 2.04-1.96 (m, 1H), 1.28 (t J=7.3, 6H). LC/MS: Anal. Calcd. for[M+H]⁺ C₁₀H₂₁N₂O₄: 233.15; found 233.24.

The synthesis of Cap-77 was conducted according to the proceduredescribed for Cap-7 by using 7-azabicyclo[2.2.1]heptane for the SN₂displacement step, and by effecting the enantiomeric separation of theintermediate benzyl 2-(7-azabicyclo[2.2.1]heptan-7-yl)-2-phenylacetateusing the following condition: the intermediate (303.7 mg) was dissolvedin ethanol, and the resulting solution was injected on a chiral HPLCcolumn (Chiracel AD-H column, 30×250 mm, 5 um) eluting with 90% CO₂-10%EtOH at 70 mL/min, and a temperature of 35° C. to provide 124.5 mg ofenantiomer-1 and 133.8 mg of enantiomer-2. These benzyl esters werehydrogenolysed according to the preparation of Cap-7 to provide Cap-77:¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 7.55 (m, 2H), 7.38-7.30 (m, 3H),4.16 (s, 1H), 3.54 (app br s, 2H), 2.08-1.88 (m, 4H), 1.57-1.46 (m, 4H).LC (Cond. 1): RT=0.67 min; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₄H₁₈NO₂:232.13; found 232.18. HRMS: Anal. Calcd. for [M+H]⁺ C₁₄H₁₈NO₂: 232.1338;found 232.1340.

NaCNBH₃ (0.5828 g, 9.27 mmol) was added to a mixture of the HCl salt of(R)-2-(ethylamino)-2-phenylacetic acid (an intermediate in the synthesisof Cap-3; 0.9923 mg, 4.60 mmol) and(1-ethoxycyclopropoxy)trimethylsilane (1.640 g, 9.40 mmol) in MeOH (10mL), and the semi-heterogeneous mixture was heated at 50° C. with an oilbath for 20 hr. More (1-ethoxycyclopropoxy)trimethylsilane (150 mg, 0.86mmol) and NaCNBH₃ (52 mg, 0.827 mmol) were added and the reactionmixture was heated for an additional 3.5 hr. It was then allowed to coolto ambient temperature and acidified to a ˜pH region of 2 withconcentrated HCl, and the mixture was filtered and the filtrate wasrotervaped. The resulting crude material was taken up in i-PrOH (6 mL)and heated to effect dissolution, and the non-dissolved part wasfiltered off and the filtrate concentrated in vacuo. About ⅓ of theresultant crude material was purified with a reverse phase HPLC(H₂O/MeOH/TFA) to afford the TFA salt of Cap-78 as a colorless viscousoil (353 mg). ¹H NMR (DMSO-d₆, 8=2.5 ppm, 400 MHz; after D₂O exchange):δ 7.56-7.49 (m, 5H), 5.35 (S, 1H), 3.35 (m, 1H), 3.06 (app br s, 1H),2.66 (m, 1H), 1.26 (t, J=7.3, 3H), 0.92 (m, 1H), 0.83-0.44 (m, 3H). LC(Cond. 1): RT=0.64 min; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₃H₁₈NO₂:220.13; found 220.21. HRMS: Anal. Calcd. for [M+H]⁺ C₁₃H₁₈NO₂: 220.1338;found 220.1343.

Ozone was bubbled through a cooled (−78° C.) CH₂Cl₂ (5.0 mL) solutionCap-55 (369 mg, 2.13 mmol) for about 50 min until the reaction mixtureattained a tint of blue color. Me₂S (10 pipet drops) was added, and thereaction mixture was stirred for 35 min. The −78° C. bath was replacedwith a −10° C. bath and stirring continued for an additional 30 min, andthen the volatile component was removed in vacuo to afford a colorlessviscous oil.

NaBH₃CN (149 mg, 2.25 mmol) was added to a MeOH (5.0 mL) solution of theabove crude material and morpholine (500 μL, 5.72 mmol) and the mixturewas stirred at ambient condition for 4 hr. It was cooled to ice-watertemperature and treated with concentrated HCl to bring its pH to 2.0,and then stirred for 2.5 hr. The volatile component was removed invacuo, and the residue was purified with a combination of MCX resin(MeOH wash; 2.0 N NH₃/MeOH elution) and a reverse phase HPLC(H₂O/MeOH/TFA) to afford Cap-79 containing unknown amount of morpholine.

In order to consume the morpholine contaminant, the above material wasdissolved in CH₂Cl₂ (1.5 mL) and treated with Et₃N (0.27 mL, 1.94 mmol)followed by acetic anhydride (0.10 mL, 1.06 mmol) and stirred at ambientcondition for 18 hr. THF (1.0 mL) and H₂O (0.5 mL) were added andstirring continued for 1.5 hr. The volatile component was removed invacuo, and the resultant residue was passed through MCX resin (MeOHwash; 2.0 N NH₃/MeOH elution) to afford impure Cap-79 as a brown viscousoil, which was used for the next step without further purification.

SOCl₂ (6.60 mL, 90.5 mmol) was added drop-wise over 15 min to a cooled(ice-water) mixture of (S)-3-amino-4-(benzyloxy)-4-oxobutanoic acid(10.04 g, 44.98 mmol) and MeOH (300 mL), the cooling bath was removedand the reaction mixture was stirred at ambient condition for 29 hr.Most of the volatile component was removed in vacuo and the residue wascarefully partitioned between EtOAc (150 mL) and saturated NaHCO₃solution. The aqueous phase was extracted with EtOAc (150 mL, 2×), andthe combined organic phase was dried (MgSO₄), filtered, and concentratedin vacuo to afford (S)-1-benzyl 4-methyl 2-aminosuccinate as a colorlessoil (9.706 g). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 7.40-7.32 (m,5H), 5.11 (s, 2H), 3.72 (app t, J=6.6, 11H), 3.55 (s, 3H), 2.68 (dd,J=15.9, 6.3, 1H), 2.58 (dd, J=15.9, 6.8, 1H), 1.96 (s, 2H). LC (Cond.1): RT=0.90 min; LC/MS: Anal. Calcd. for [M+H]⁺ C₁₂H₁₆NO₄: 238.11; found238.22.

Pb(NO₃)₂ (6.06 g, 18.3 mmol) was added over 1 min to a CH₂Cl₂ (80 mL)solution of (S)-1-benzyl 4-methyl 2-aminosuccinate (4.50 g, 19.0 mmol),9-bromo-9-phenyl-9H-fluorene (6.44 g, 20.0 mmol) and Et₃N (3.0 mL, 21.5mmol), and the heterogeneous mixture was stirred at ambient conditionfor 48 hr. The mixture was filtered and the filtrate was treated withMgSO₄ and filtered again, and the final filtrate was concentrated. Theresulting crude material was submitted to a Biotage purification (350 gsilica gel, CH₂Cl₂ elution) to afford (S)-1-benzyl 4-methyl2-(9-phenyl-9H-fluoren-9-ylamino)succinate as highly viscous colorlessoil (7.93 g). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): δ 7.82 (m, 2H),7.39-7.13 (m, 16H), 4.71 (d, J=12.4, 1H), 4.51 (d, J=12.6, 1H), 3.78 (d,J=9.1, NH), 3.50 (s, 3H), 2.99 (m, 1H), 2.50-2.41 (m, 2H, partiallyoverlapped with solvent). LC (Cond. 1): RT=2.16 min; LC/MS: Anal. Calcd.for [M+H]⁺ C₃₁H₂₈NO₄: 478.20; found 478.19.

LiHMDS (9.2 mL of 1.0 M/THF, 9.2 mmol) was added drop-wise over 10 minto a cooled (−78° C.) THF (50 mL) solution of (S)-1-benzyl 4-methyl2-(9-phenyl-9H-fluoren-9-ylamino)succinate (3.907 g, 8.18 mmol) andstirred for ˜1 hr. MeI (0.57 mL, 9.2 mmol) was added drop-wise over 8min to the mixture, and stirring was continued for 16.5 hr whileallowing the cooling bath to thaw to room temperature. After quenchingwith saturated NH₄Cl solution (5 mL), most of the organic component wasremoved in vacuo and the residue was partitioned between CH₂Cl₂ (100 mL)and water (40 mL). The organic layer was dried (MgSO₄), filtered, andconcentrated in vacuo, and the resulting crude material was purifiedwith a Biotage (350 g silica gel; 25% EtOAc/hexanes) to afford 3.65 g ofa 2S/3S and 2S/3R diastereomeric mixtures of 1-benzyl 4-methyl3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)succinate in ˜1.0:0.65 ratio(¹H NMR). The stereochemistry of the dominant isomer was not determinedat this juncture, and the mixture was submitted to the next step withoutseparation. Partial ¹H NMR data (DMSO-d₆, δ=2.5 ppm, 400 MHz): majordiastereomer, δ 4.39 (d, J=12.3, 1H of CH₂), 3.33 (s, 3H, overlappedwith H₂O signal), 3.50 (d, J=10.9, NH), 1.13 (d, J=7.1, 3H); minordiastereomer, δ 4.27 (d, J=12.3, 1H of CH₂), 3.76 (d, J=10.9, NH), 3.64(s, 3H), 0.77 (d, J 7.0, 3H). LC (Cond. 1): RT=2.19 min; LC/MS: Anal.Calcd. for [M+H]⁺ C₃₂H₃₀NO₄: 492.22; found 492.15.

Diisobutylaluminum hydride (20.57 ml of 1.0 M in hexanes, 20.57 mmol)was added drop-wise over 10 min to a cooled (−78° C.) THF (120 mL)solution of (2S)-1-benzyl 4-methyl3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)succinate (3.37 g, 6.86 mmol)prepared above, and stirred at −78° C. for 20 hr. The reaction mixturewas removed from the cooling bath and rapidly poured into ˜1M H₃PO₄/H₂O(250 mL) with stirring, and the mixture was extracted with ether (100mL, 2×). The combined organic phase was washed with brine, dried(MgSO₄), filtered and concentrated in vacuo. A silica gel mesh of thecrude material was prepared and submitted to chromatography (25%EtOAc/hexanes; gravity elution) to afford 11.1 g of (2S,3S)-benzyl4-hydroxy-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate,contaminated with benzyl alcohol, as a colorless viscous oil and(2S,3R)-benzyl4-hydroxy-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate containingthe (2S,3R) stereoisomer as an impurity. The later sample wasresubmitted to the same column chromatography purification conditions toafford 750 mg of purified material as a white foam. [Note: the (2S,3S)isomer elutes before the (2S,3R) isomer under the above condition].(2S,3S) isomer: ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): 7.81 (m, 2H),7.39-7.08 (m, 16H), 4.67 (d, J=12.3, 1H), 4.43 (d, J=12.4, 11H), 4.21(app t, J=5.2, OH), 3.22 (d, J=10.1, NH), 3.17 (m, 1H), 3.08 (m, 1H),˜2.5 (m, 1H, overlapped with the solvent signal), 1.58 (m, 1H), 0.88 (d,J=6.8, 3H). LC (Cond. 1): RT=2.00 min; LC/MS: Anal. Calcd. for [M+H]⁺C₃₁H₃₀NO₃: 464.45; found 464.22. (2S,3R) isomer: ¹H NMR (DMSO-d₆, δ=2.5ppm, 400 MHz): 7.81 (d, J=7.5, 2H), 7.39-7.10 (m, 16H), 4.63 (d, J=12.1,1H), 4.50 (app t, J=4.9, 1H), 4.32 (d, J=12.1, 11H), 3.59-3.53 (m, 2H),3.23 (m, 1H), 2.44 (dd, J=9.0, 8.3, 1H), 1.70 (m, 1H), 0.57 (d, J=6.8,3H). LC (Cond. 1): RT=1.92 min; LCMS: Anal. Calcd. for [M+H]⁺ C₃₁H₃₀NO₃:464.45; found 464.52.

The relative stereochemical assignments of the DIBAL-reduction productswere made based on NOE studies conducted on lactone derivatives preparedfrom each isomer by employing the following protocol: LiHMDS (50 μL of1.0 M/THF, 0.05 mmol) was added to a cooled (ice-water) THF (2.0 mL)solution of (2S,3S)-benzyl4-hydroxy-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate (62.7 mg,0.135 mmol), and the reaction mixture was stirred at similar temperaturefor ˜2 hr. The volatile component was removed in vacuo and the residuewas partitioned between CH₂Cl₂ (30 mL), water (20 mL) and saturatedaqueous NH₄Cl solution (1 mL). The organic layer was dried (MgSO₄),filtered, and concentrated in vacuo, and the resulting crude materialwas submitted to a Biotage purification (40 g silica gel; 10-15%EtOAc/hexanes) to afford(3S,4S)-4-methyl-3-(9-phenyl-9H-fluoren-9-ylamino)dihydrofuran-2(3H)-oneas a colorless film of solid (28.1 mg). (2S,3R)-benzyl4-hydroxy-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate waselaborated similarly to(3S,4R)-4-methyl-3-(9-phenyl-9H-fluoren-9-ylamino)dihydrofuran-2(3H)-one.(3S,4S)-lactone isomer: ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz), 7.83 (d,J=7.5, 2H), 7.46-7.17 (m, 11H), 4.14 (app t, J=8.3, 1H), 3.60 (d, J=5.8,NH), 3.45 (app t, J=9.2, 1H), 2.47 (m, 1H, partially overlapped withsolvent signal), 2.16 (m, 1H), 0.27 (d, J=6.6, 3H). LC (Cond. 1):RT=1.98 min; LC/MS: Anal. Calcd. for [M+Na]⁺ C₂₄H₂₁NNaO₂: 378.15; found378.42. (3S,4R)-lactone isomer: ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz),7.89 (d, J=7.6, 1H), 7.85 (d, J=7.3, 1H), 7.46-7.20 (m, 11H), 3.95 (dd,J=9.1, 4.8, 1H), 3.76 (d, J=8.8, 11H), 2.96 (d, J=3.0, NH), 2.92 (dd,J=6.8, 3, NCH), 1.55 (m, 1H), 0.97 (d, J=7.0, 3H). LC (Cond. 1): RT=2.03min; LC/MS: Anal. Calcd. for [M+Na]⁻ C₂₄H₂₁NNaO₂: 378.15; found 378.49.

TBDMS-Cl (48 mg, 0.312 mmol) followed by imidazole (28.8 mg, 0.423 mmol)were added to a CH₂Cl₂ (3 ml) solution of (2S,3S)-benzyl4-hydroxy-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate (119.5 mg,0.258 mmol), and the mixture was stirred at ambient condition for 14.25hr. The reaction mixture was then diluted with CH₂Cl₂ (30 mL) and washedwith water (15 mL), and the organic layer was dried (MgSO₄), filtered,and concentrated in vacuo. The resultant crude material was purifiedwith a Biotage (40 g silica gel; 5% EtOAc/hexanes) to afford(2S,3S)-benzyl4-(tert-butyldimethylsilyloxy)-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate,contaminated with TBDMS based impurities, as a colorless viscous oil(124.4 mg). (2S,3R)-benzyl4-hydroxy-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate waselaborated similarly to (2S,3R)-benzyl4-(tert-butyldimethylsilyloxy)-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate.(2S,3S)-silyl ether isomer: ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz), 7.82(d, J=4.1, 1H), 7.80 (d, J=4.0, 1H), 7.38-7.07 (m, 16H), 4.70 (d,J=12.4, 1H), 4.42 (d, J=12.3, 1H), 3.28-3.19 (m, 3H), 2.56 (dd, J=10.1,5.5, 1H), 1.61 (m, 1H), 0.90 (d, J=6.8, 3H), 0.70 (s, 9H), −0.13 (s,3H), −0.16 (s, 3H). LC (Cond. 1, where the run time was extended to 4ml): RT=3.26 mm; LC/MS: Anal. Calcd. for [M+]⁺ C₃₇H₄₄NO₃Si: 578.31;found 578.40. (2S,3R)-silyl ether isomer: ¹H NMR (DMSO-d₆, δ=2.5 ppm,400 MHz), 7.82 (d, J=3.0, 1H), 7.80 (d, J=3.1, 1H), 7.39-7.10 (m, 16H),4.66 (d, J=12.4, 1H), 4.39 (d, J=12.4, 1H), 3.61 (dd, J=9.9, 5.6, 1H),3.45 (d, J=9.5, 1H), 3.41 (dd, J=10, 6.2, 1H), 2.55 (dd, J=9.5, 7.3,1H), 1.74 (m, 1H), 0.77 (s, 9H), 0.61 (d, J=7.1, 3H), −0.06 (s, 3H),−0.08 (s, 3H).

A balloon of hydrogen was attached to a mixture of (2S,3S)-benzyl4-(tert-butyldimethylsilyloxy)-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoate(836 mg, 1.447 mmol) and 10% Pd/C (213 mg) in EtOAc (16 mL) and themixture was stirred at room temperature for ˜21 hr, where the balloonwas recharged with H₂ as necessary. The reaction mixture was dilutedwith CH₂Cl₂ and filtered through a pad of diatomaceous earth(CELITE®-545), and the pad was washed with EtOAc (200 mL), EtOAc/MeOH(1:1 mixture, 200 mL) and MeOH (750 mL). The combined organic phase wasconcentrated, and a silica gel mesh was prepared from the resultingcrude material and submitted to a flash chromatography (8:2:1 mixture ofEtOAc/1-PrOH/H₂O) to afford(2S,3S)-2-amino-4-(tert-butyldimethylsilyloxy)-3-methylbutanoic acid asa white fluffy solid (325 mg). (2S,3R)-benzyl4-(tert-butyldimethylsilyloxy)-3-methyl-2-(9-phenyl-9H-fluoren-9-ylamino)butanoatewas similarly elaborated to(2S,3R)-2-amino-4-(tert-butyldimethylsilyloxy)-3-methylbutanoic acid.(2S,3S)-amino acid isomer: ¹H NMR (Methanol-d₄, δ=3.29 ppm, 400 MHz),3.76 (dd, J=10.5, 5.2, 1H), 3.73 (d, J=3.0, 1H), 3.67 (dd, J=10.5, 7.0,1H), 2.37 (m, 1H), 0.97 (d, J=7.0, 3H), 0.92 (s, 9H), 0.10 (s, 6H).LC/MS: Anal. Calcd. for [M+H]⁺ C₁₁H₂₆NO₃Si: 248.17; found 248.44.(2S,3R)-amino acid isomer: ¹H NMR (Methanol-d₄, δ=3.29 ppm, 400 MHz),3.76-3.75 (m, 2H), 3.60 (d, J=4.1, 1H), 2.16 (m, 1H), 1.06 (d, J=7.3,3H), 0.91 (s, 9H), 0.09 (s, 6H). Anal. Calcd. for [M+H]⁺ C₁₁H₂₆NO₃Si:248.17; found 248.44.

Water (1 mL) and NaOH (0.18 mL of 1.0 M/H₂O, 0.18 mmol) were added to amixture of(2S,3S)-2-amino-4-(tert-butyldimethylsilyloxy)-3-methylbutanoic acid(41.9 mg, 0.169 mmol) and Na₂CO₃ (11.9 mg, 0.112 mmol), and sonicatedfor about 1 min to effect dissolution of reactants. The mixture was thencooled with an ice-water bath, methyl chloroformate (0.02 mL, 0.259mmol) was added over 30 s, and vigorous stirring was continued atsimilar temperature for 40 min and then at ambient temperature for 2.7hr. The reaction mixture was diluted with water (5 mL), cooled withice-water bath and treated drop-wise with 1.0 N HCl aqueous solution(˜0.23 mL). The mixture was further diluted with water (10 mL) andextracted with CH₂Cl₂ (15 mL, 2×). The combined organic phase was dried(MgSO₄), filtered, and concentrated in vacuo to afford Cap-80a as anoff-white solid.(2S,3R)-2-amino-4-(tert-butyldimethylsilyloxy)-3-methylbutanoic acid wassimilarly elaborated to Cap-80b. Cap-80a: ¹H NMR (DMSO-d₆, δ=2.5 ppm,400 MHz), 12.57 (br s, 1H), 7.64 (d, J=8.3, 0.3H), 7.19 (d, J=8.8,0.7H), 4.44 (dd, J=8.1, 4.6, 0.3H), 4.23 (dd, J=8.7, 4.4, 0.7H),3.56/3.53 (two singlets, 3H), 3.48-3.40 (m, 2H), 2.22-2.10 (m, 1H), 0.85(s, 9H), 0.84 (d, 0.9H, overlapped with t-Bu signal), 0.79 (d, J=7,2.1H), 0.02/0.01/0.00 (three overlapping singlets, 6H). LC/MS: Anal.Calcd. for [M+Na]⁺ C₁₃H₂₇NNaO₅Si: 328.16; found 328.46. Cap-80b: ¹H NMR(CDCl₃, δ=7.24 ppm, 400 MHz), 6.0 (br d, J=6.8, 1H), 4.36 (dd, J=7.1,3.1, 1H), 3.87 (dd, J=10.5, 3.0, 1H), 3.67 (s, 3H), 3.58 (dd, J=10.6,4.8, 1H), 2.35 (m, 1H), 1.03 (d, J=7.1, 3H), 0.90 (s, 9H), 0.08 (s, 6H).LC/MS: Anal. Calcd. for [M+Na]⁺ C₁₃H₂₇NNaO₅Si: 328.16; found 328.53. Thecrude products were utilized without further purification.

Prepared according to the protocol described by Falb et al. SyntheticCommunications 1993, 23, 2839.

Cap-82 to Cap-85

Cap-82 to Cap-85 were synthesized from appropriate starting materialsaccording to the procedure described for Cap-51 or Cap-13. The samplesexhibited similar spectral profiles as that of their enantiomers (i.e.,Cap-4, Cap-13, Cap-51 and Cap-52, respectively).

To a mixture of O-methyl-L-threonine (3.0 g, 22.55 mmol), NaOH (0.902 g,22.55 mmol) in H₂O (15 mL) was added ClCO₂Me (1.74 mL, 22.55 mmol)dropwise at 0° C. The mixture was allowed to stir for 12 h and acidifiedto pH 1 using 1N HCl. The aqueous phase was extracted with EtOAc and(2×250 mL) and 10% MeOH in CH₂Cl₂ (250 mL) and the combined organicphases were concentrated under in vacuo to afford a colorless oil (4.18g, 97%) which was of sufficient purity for use in subsequent steps. ¹HNMR (400 MHz, CDCl₃) δ4.19 (s, 1H), 3.92-3.97 (m, 1H), 3.66 (s, 3H),1.17 (d, J=7.7 Hz, 3H). LCMS: Anal. Calcd. for C₇H₁₃NO₅: 191; found: 190(M−H)⁻.

To a mixture of L-homoserine (2.0 g, 9.79 mmol), Na₂CO₃ (2.08 g, 19.59mmol) in H₂O (15 mL) was added ClCO₂Me (0.76 mL, 9.79 mmol) dropwise at0° C. The mixture was allowed to stir for 48 h and acidified to pH 1using 1N HCl. The aqueous phase was extracted with EtOAc and (2×250 mL)and the combined organic phases were concentrated in vacuo to afford acolorless solid (0.719 g, 28%) which was of sufficient purity for use insubsequent steps. ¹H NMR (400 MHz, CDCl₃) δ 4.23 (dd, J=4.5, 9.1 Hz,1H), 3.66 (s, 3H), 3.43-3.49 (m, 2H), 2.08-2.14 (m, 1H), 1.82-1.89 (m,1H). LCMS: Anal. Calcd. for C₇H₁₃NO₅:191; found: 192 (M+H)⁺.

A mixture of L-valine (1.0 g, 8.54 mmol), 3-bromopyridine (1.8 mL, 18.7mmol), K₂CO₃ (2.45 g, 17.7 mmol) and CuI (169 mg, 0.887 mmol) in DMSO(10 mL) was heated at 100° C. for 12 h. The reaction mixture was cooledto rt, poured into H₂O (ca. 150 mL) and washed with EtOAc (×2). Theorganic layers were extracted with a small amount of H₂O and thecombined aq phases were acidified to ca. pH 2 with 6N HCl. The volumewas reduced to about one-third and 20 g of cation exchange resin(Strata) was added. The slurry was allowed to stand for 20 min andloaded onto a pad of cation exchange resin (Strata) (ca. 25 g). The padwas washed with H₂O (200 mL), MeOH (200 mL), and then NH₃ (3M in MeOH,2×200 mL). The appropriate fractions was concentrated in vacuo and theresidue (ca. 1.1 g) was dissolved in H₂O, frozen and lyophyllized. Thetitle compound was obtained as a foam (1.02 g, 62%). ¹H NMR (400 MHz,DMSO-d₆) δ 8.00 (s, br, 1H), 7.68-7.71 (m, 1H), 7.01 (s, br, 1H), 6.88(d, J=7.5 Hz, 1H), 5.75 (s, br, 1H), 3.54 (s, 1H), 2.04-2.06 (m, 1H),0.95 (d, J=6.0 Hz, 3H), 0.91 (d, J=6.6 Hz, 3H). LCMS: Anal. Calcd. forC₁₀H₁₄N₂O₂: 194; found: 195 (M+H)⁺.

A mixture of L-valine (1.0 g, 8.54 mmol), 5-bromopyrimidine (4.03 g,17.0 mmol), K₂CO₃ (2.40 g, 17.4 mmol) and CuI (179 mg, 0.94 mmol) inDMSO (10 mL) was heated at 100° C. for 12 h. The reaction mixture wascooled to RT, poured into H₂O (ca. 150 mL) and washed with EtOAc (×2).The organic layers were extracted with a small amount of H₂O and thecombined aq phases were acidified to ca. pH 2 with 6N HCl. The volumewas reduced to about one-third and 20 g of cation exchange resin(Strata) was added. The slurry was allowed to stand for 20 min andloaded onto a pad of cation exchange resin (Strata) (ca. 25 g). The padwas washed with H₂O (200 mL), MeOH (200 mL), and then NH₃ (3M in MeOH,2×200 mL). The appropriate fractions was concentrated in vacuo and theresidue (ca. 1.1 g) was dissolved in H₂O, frozen and lyophyllized. Thetitle compound was obtained as a foam (1.02 g, 62%). ¹H NMR (400 MHz,CD₃OD) showed the mixture to contain valine and the purity could not beestimated. The material was used as is in subsequent reactions. LCMS:Anal. Calcd. for C₉H₁₃N₃O₂: 195; found: 196 (M+H)⁺.

Cap-90 was prepared according to the method described for thepreparation of Cap-1. The crude material was used as is in subsequentsteps. LCMS: Anal, Calcd. for C₁₁H₁₅NO₂: 193; found: 192 (M−H)⁻.

The following caps were prepared according to the method used forpreparation of cap 51 unless noted otherwise:

Cap Structure LCMS Cap-91

LCMS: Anal. Calcd. for C₁₁H₁₃NO₄: 223; found: 222 (M − H)⁻. Cap-92

LCMS: Anal. Calcd. for C₁₁H₁₃NO₄: 223; found: 222 (M − H)⁻. Cap-93

LCMS: Anal. Calcd. for C₁₀H₁₂N₂O₄: 224; found: 225 (M + H)⁺. Cap-94

LCMS: Anal. Calcd. for C₈H₁₁N₃O₄: 213; found: 214 (M + H)⁺. Cap-95

LCMS: Anal. Calcd. for C₁₃H₁₇NO₄: 251; found: 250 (M − H)⁻. Cap-96

LCMS: Anal. Calcd. for C₁₂H₁₅NO₄: 237; found: 236 (M − H)⁻. Cap-97

LCMS: Anal. Calcd. for C₉H₁₅NO₄: 201; found: 200 (M − H)⁻. Cap-98

LCMS: Anal. Calcd. for C₉H₁₅NO₄: 201; found: 202 (M + H)⁺. Cap-99

¹H NMR (400 MHz, CD₃OD) δ 3.88-3.94 (m, 1H), 3.60, 3.61 (s, 3H), 2.80(m, 1H), 2.20 (m, 1H), 1.82-1.94 (m, 3H), 1.45-1.71 (m, 2H). Cap-99a

¹H NMR (400 MHz, CD₃OD) δ 3.88-3.94 (m, 1H), 3.60, 3.61 (s, 3H), 2.80(m, 1H), 2.20 (m, 1H), 1.82-1.94 (m, 3H), 1.45-1.71 (m, 2H). Cap-100

LCMS: Anal. Calcd. for C₁₂H₁₄NO₄F: 255; found: 256 (M + H)⁺. Cap-101

LCMS: Anal. Calcd. for C₁₁H₁₃NO₄: 223; found: 222 (M − H)⁻. Cap-102

LCMS: Anal. Calcd. for C₁₁H₁₃NO₄: 223; found: 222 (M − H)⁻ Cap-103

LCMS: Anal. Calcd. for C₁₀H₁₂N₂O₄: 224; found: 225 (M + H)⁺. Cap-104

¹H NMR (400 MHz, CD₃OD) δ 3.60 (s, 3H), 3.50-3.53 (m, 1H), 2.66-2.69 and2.44-2.49 (m, 1H), 1.91-2.01 (m, 2H), 1.62-1.74 (m, 4H), 1.51-1.62 (m,2H). Cap-105

¹H NMR (400 MHz, CD₃OD) δ 3.60 (s, 3H), 3.33-3.35 (m, 1H, partiallyobscured by solvent), 2.37-2.41 and 2.16-2.23 (m, 1H), 1.94-2.01 (m,4H), 1.43-1.53 (m, 2H), 1.17-1.29 (m, 2H). Cap-106

¹H NMR (400 MHz, CD₃OD) δ 3.16 (q, J = 7.3 Hz, 4H), 2.38-2.41 (m, 1H),2.28-2.31 (m, 2H), 1.79-1.89 (m, 2H), 1.74 (app, ddd J = 3.5, 12.5, 15.9Hz, 2H), 1.46 (app dt J = 4.0, 12.9 Hz, 2H), 1.26 (t, J = 7.3 Hz, 6H)Cap-107

LCMS: Anal. Calcd. for C₈H₁₀N₂O₄S: 230; found: 231 (M + H)⁺. Cap-108

LCMS: Anal. Calcd. for C₁₅H₁₇N₃O₄: 303; found: 304 (M + H)⁺. Cap-109

LCMS: Anal. Calcd. for C₁₀H₁₂N₂O₄: 224; found: 225 (M + H)⁺. Cap-110

LCMS: Anal. Calcd. for C₁₀H₁₂N₂O₄: 224; found: 225 (M + H)⁺. Cap-111

LCMS: Anal. Calcd. for C₁₂H₁₆NO₈P: 333; found: 334 (M + H)⁺. Cap-112

LCMS: Anal. Calcd. for C₁₃H₁₄N₂O₄: 262, found: 263 (M + H)⁺. Cap-113

LCMS: Anal. Calcd. for C₁₈H₁₉NO₅: 329; found: 330 (M + H)⁺. Cap-114

¹H NMR (400 MHz, CDCl₃) δ 4.82-4.84 (m, 1H), 4.00-4.05 (m, 2H), 3.77 (s,3H), 2.56 (s, br, 2H) Cap-115

¹H NMR (400 MHz, CDCl₃) δ 5.13 (s, br, 1H), 4.13 (s, br, 1H), 3.69 (s,3H), 2.61 (d, J = 5.0 Hz, 2H), 1.28 (d, J = 9.1 Hz, 3H). Cap-116

¹H NMR (400 MHz, CDCl₃) δ 5.10 (d, J = 8.6 Hz, 1H), 3.74-3.83 (m, 1H),3.69 (s, 3H), 2.54-2.61 (m, 2H), 1.88 (sept, J = 7.0 Hz, 1H), 0.95 (d, J= 7.0 Hz, 6H).

Cap-117 to Cap-123

For the preparation of Cap-117 to Cap-123 the Boc amino acids wereobtained from commercially sources and were deprotected by treatmentwith 25% TFA in CH₂Cl₂. After complete reaction as judged by LCMS thesolvents were removed in vacuo and the corresponding TFA salt of theamino acid was carbamoylated with methyl chloroformate according to theprocedure described for Cap-51.

Cap Structure LCMS Cap-117

LCMS: Anal. Calcd. for C₁₂H₁₅NO₄: 237; found: 238 (M + H)⁺. Cap-118

LCMS: Anal. Calcd. for C₁₀H₁₃NO₄S: 243; found: 244 (M + H)⁺. Cap-119

LCMS: Anal. Calcd. for C₁₀H₁₃NO₄S: 243; found: 244 (M + H)⁺. Cap-120

LCMS: Anal. Calcd. for C₁₀H₁₃NO₄S: 243; found: 244 (M + H)⁺. Cap-121

¹H NMR (400 MHz, CDCl₃) δ 4.06-4.16 (m, 1H), 3.63 (s, 3H), 3.43 (s, 1H),2.82 and 2.66 (s, br, 1H), 1.86-2.10 (m, 3H), 1.64-1.76 (m, 2H),1.44-1.53 (m, 1H). Cap-122

¹H NMR profile is similar to that of its enantiomer, Cap-121. Cap-123

LCMS: Anal. Calcd. for C₂₇H₂₆N₂O₆: 474; found: 475 (M + H)⁺.

The hydrochloride salt of L-threonine tert-butyl ester was carbamoylatedaccording to the procedure for Cap-51. The crude reaction mixture wasacidified with 1N HCl to pH˜1 and the mixture was extracted with EtOAc(2×50 mL). The combined organic phases were concentrated in vacuo togive a colorless oil which solidified on standing. The aqueous layer wasconcentrated in vacuo and the resulting mixture of product and inorganicsalts was triturated with EtOAc-CH₂Cl₂-MeOH (1:1:0.1) and then theorganic phase concentrated in vacuo to give a colorless oil which wasshown by LCMS to be the desired product. Both crops were combined togive 0.52 g of a solid. ¹H NMR (400 MHz, CD₃OD) δ 4.60 (m, 1H), 4.04 (d,J=5.0 Hz, 1H), 1.49 (d, J=6.3 Hz, 3H). LCMS: Anal. Calcd. for C₅H₇NO₄:145; found: 146 (M+H)⁺.

To a suspension of Pd(OH)₂, (20%, 100 mg), aqueous formaldehyde (37% wt,4 ml), acetic acid, (0.5 mL) in methanol (15 mL) was added(S)-4-amino-2-(tert-butoxycarbonylamino)butanoic acid (1 g, 4.48 mmol).The reaction was purged several times with hydrogen and was stirredovernight with an hydrogen balloon room temp. The reaction mixture wasfiltered through a pad of diatomaceous earth (CELITE®), and the volatilecomponent was removed in vacuo. The resulting crude material was used asis for the next step. LC/MS: Anal. Calcd. for C₁₁H₂₂N₂O₄: 246; found:247 (M+H)⁺.

This procedure is a modification of that used to prepare Cap-51. To asuspension of 3-methyl-L-histidine (0.80 g, 4.70 mmol) in THF (10 mL)and H₂O (10 mL) at 0° C. was added NaHCO₃ (0.88 g, 10.5 mmol). Theresulting mixture was treated with ClCO₂Me (0.40 mL, 5.20 mmol) and themixture allowed to stir at 0° C. After stirring for ca. 2 h LCMS showedno starting material remaining. The reaction was acidified to pH 2 with6 N HCl.

The solvents were removed in vacuo and the residue was suspended in 20mL of 20% MeOH in CH₂Cl₂. The mixture was filtered and concentrated togive a light yellow foam (1.21 g,). LCMS and ¹H NMR showed the materialto be a 9:1 mixture of the methyl ester and the desired product. Thismaterial was taken up in THF (10 mL) and H₂O (10 mL), cooled to 0° C.and LiOH (249.1 mg, 10.4 mmol) was added. After stirring ca. 1 h LCMSshowed no ester remaining. Therefore the mixture was acidified with 6NHCl and the solvents removed in vacuo. LCMS and ¹H NMR confirm theabsence of the ester. The title compound was obtained as its HCl saltcontaminated with inorganic salts (1.91 g, >100%). The compound was usedas is in subsequent steps without further purification. ¹H NMR (400 MHz,CD₃OD) δ 8.84, (s, 1H), 7.35 (s, 1H), 4.52 (dd, J=5.0, 9.1 Hz, 1H), 3.89(s, 3H), 3.62 (s, 3H), 3.35 (dd, J=4.5, 15.6 Hz, 1H, partially obscuredby solvent), 3.12 (dd, J=9.0, 15.6 Hz, 1H).LCMS: Anal. Calcd. forC₉H₁₃N₃O₄: 227.09; found: 228.09 (M+H)⁺.

Cap-127 was prepared according to the method for Cap-126 above startingfrom (S)-2-amino-3-(1-methyl-1H-imidazol-4-yl)propanoic acid (1.11 g,6.56 mmol), NaHCO₃ (1.21 g, 14.4 mmol) and ClCO₂Me (0.56 mL, 7.28 mmol).The title compound was obtained as its HCl salt (1.79 g, >100%)contaminated with inorganic salts. LCMS and ¹H NMR showed the presenceof ca. 5% of the methyl ester. The crude mixture was used as is withoutfurther purification. ¹H NMR (400 MHz, CD₃OD) δ 8.90 (s, 1H), 7.35 (s,1H), 4.48 (dd, J=5.0, 8.6 Hz, 1H), 3.89 (s, 3H), 3.62 (s, 3H), 3.35 (m,1H), 3.08 (m, 1H); LCMS: Anal. Calcd. for C₉H₁₃N₃O₄: 227.09; found: 228(M+H)⁺.

Step 1. Preparation of (S)-benzyl2-(tert-butoxycarbonylamino)pent-4-ynoate (cj-27b)

To a solution of cj-27a (1.01 g, 4.74 mmol), DMAP (58 mg, 0.475 mmol)and iPr₂NEt (1.7 mL, 9.8 mmol) in CH₂Cl₂ (100 mL) at 0° C. was addedCbz-Cl (0.68 mL, 4.83 mmol). The solution was allowed to stir for 4 h at0° C., washed (1N KHSO₄, brine), dried (Na₂SO₄), filtered, andconcentrated in vacuo. The residue was purified by flash columnchromatography (TLC 6:1 hex:EtOAc) to give the title compound (1.30 g,91%) as a colorless oil. ¹H NMR (400 MHz, CDCl₃) δ 7.35 (s, 5H), 5.35(d, br, J=8.1 Hz, 1H), 5.23 (d, J=12.2 Hz, 1H), 5.17 (d, J=12.2 Hz, 1H),4.48-4.53 (m, 1H), 2.68-2.81 (m, 2H), 2.00 (t, J=2.5 Hz, 1H), 1.44 (s,9H). LCMS: Anal. Calcd. for C₁₇H₂₁NO₄: 303; found: 304 (M+H)⁺.

Step 2. Preparation of (S)-benzyl3-(1-benzyl-1H-1,2,3-triazol-4-yl)-2-(tert-butoxycarbonylamino)propanoate(cj-28)

To a mixture of (S)-benzyl 2-(tert-butoxycarbonylamino)pent-4-ynoate(0.50 g, 1.65 mmol), sodium ascorbate (0.036 g, 0.18 mmol), CuSO₄-5H₂O(0.022 g, 0.09 mmol) and NaN₃ (0.13 g, 2.1 mmol) in DMF-H₂O (5 mL, 4:1)at rt was added BnBr (0.24 mL, 2.02 mmol) and the mixture was warmed to65° C. After 5 h LCMS indicated low conversion. A further portion ofNaN₃ (100 mg) was added and heating was continued for 12 h. The reactionwas poured into EtOAc and 1H₂O and shaken. The layers were separated andthe aqueous layer extracted 3× with EtOAc and the combined organicphases washed (H₂O x3, brine), dried (Na₂SO₄), filtered, andconcentrated. The residue was purified by flash (Biotage, 40+M 0-5% MeOHin CH₂Cl₂; TLC 3% MeOH in CH₂Cl₂) to afford a light yellow oil whichsolidified on standing (748.3 mg, 104%). The NMR was consistent with thedesired product but suggests the presence of DMF. The material was usedas is without further purification. ¹H NMR (400 MHz, DMSO-d₆) δ 7.84 (s,1H), 7.27-7.32 (m, 10H), 5.54 (s, 2H), 5.07 (s, 2H), 4.25 (m, 1H), 3.16(dd, J=1.0, 5.3 Hz, 1H), 3.06 (dd, J=5.3, 14.7 Hz), 2.96 (dd, J=9.1,14.7 Hz, 1H), 1.31 (s, 9H). LCMS: Anal. Calcd. for C₂₄H₂₈N₄O₄; 436;found: 437 (M+H)⁺.

Step 3. Preparation of (S)-benzyl3-(1-benzyl-1H-1,2,3-triazol-4-yl)-2-(methoxycarbonylamino)propanoate(cj-29)

A solution of (S)-benzyl3-(1-benzyl-1H-1,2,3-triazol-4-yl)-2-(tert-butoxycarbonylamino)propanoate(0.52 g, 1.15 mmol) in CH₂Cl₂ was added TFA (4 mL). The mixture wasallowed to stir at room temperature for 2 h. The mixture wasconcentrated in vacuo to give a colorless oil which solidified onstanding. This material was dissolved in THF—H₂O and cooled to 0° C.Solid NaHCO₃ (0.25 g, 3.00 mmol) was added followed by ClCO₂Me (0.25 mL,3.25 mmol). After stirring for 1.5 h the mixture was acidified to pH˜2with 6N HCl and then poured into H₂O-EtOAc. The layers were separatedand the aq phase extracted 2× with EtOAc. The combined org layers werewashed (H₂O, brine), dried (Na₂SO₄), filtered, and concentrated in vacuoto give a colorless oil (505.8 mg, 111%, NMR suggested the presence ofan unidentified impurity) which solidified while standing on the pump.The material was used as is without further purification. ¹H NMR (400MHz, DMSO-d₆) δ 7.87 (s, 1H), 7.70 (d, J=8.1 Hz, 1H), 7.27-7.32 (m,10H), 5.54 (s, 2H), 5.10 (d, J=12.7 Hz, 1H), 5.06 (d, J=12.7 Hz, 1H),4.32-4.37 (m, 1H), 3.49 (s, 3H), 3.09 (dd, J=5.6, 14.7 Hz, 1H), 2.98(dd, J=9.6, 14.7 Hz, 1H). LCMS: Anal. Calcd. for C₂₁H₂₂N₄O₄: 394; found:395 (M+H)⁺.

Step 4. Preparation of(S)-2-(methoxycarbonylamino)-3-(1H-1,2,3-triazol-4-yl)propanoic acid(Cap-128)

(S)-benzyl3-(1-benzyl-1H-1,2,3-triazol-4-yl)-2-(methoxycarbonylamino)propanoate(502 mg, 1.11 mmol) was hydrogenated in the presence of Pd—C (82 mg) inMeOH (5 mL) at atmospheric pressure for 12 h. The mixture was filteredthrough diatomaceous earth (CELITE®) and concentrated in vacuo.(S)-2-(methoxycarbonylamino)-3-(1H-1,2,3-triazol-4-yl)propanoic acid wasobtained as a colorless gum (266 mg, 11%) which was contaminated withca. 10% of the methyl ester. The material was used as is without furtherpurification. ¹H NMR (400 MHz, DMSO-d₆) δ 12.78 (s, br, 1H), 7.59 (s,1H), 7.50 (d, J=8.0 Hz, 1H), 4.19-4.24 (m, 1H), 3.49 (s, 3H), 3.12 (dd,J=4.8 Hz, 14.9 Hz, 1H), 2.96 (dd, J=9.9, 15.0 Hz, 1H). LCMS: Anal.Calcd. for C₇H₁₁N₄O₄: 214; found: 215 (M+H)⁺.

Step 1. Preparation of(S)-2-(benzyloxycarbonylamino)-3-(1H-pyrazol-1-yl)propanoic acid (cj-31)

A suspension of (S)-benzyl 2-oxooxetan-3-ylcarbamate (0.67 g, 3.03mmol), and pyrazole (0.22 g, 3.29 mmol) in CH₃CN (12 mL) was heated at50° C. for 24 h. The mixture was cooled to rt overnight and the solidfiltered to afford(S)-2-(benzyloxycarbonylamino)-3-(1H-pyrazol-1-yl)propanoic acid (330.1mg). The filtrate was concentrated in vacuo and then triturated with asmall amount of CH₃CN (ca. 4 mL) to afford a second crop (43.5 mg).Total yield 370.4 mg (44%). m.p. 165.5-168° C. lit m.p. 168.5-169.5[Vederas et al. J. Am. Chem. Soc. 1985, 107, 7105]. ¹H NMR (400 MHz,CD₃OD) δ7.51 (d, J=2.0, 1H), 7.48 (s, J=1.5 Hz, 1H), 7.24-7.34 (m, 5H),6.23 m, 1H), 5.05 (d, 12.7H, 1H), 5.03 (d, J=12.7 Hz, 1H), 4.59-4.66 (m,2H), 4.42-4.49 (m, 1H). LCMS: Anal. Calcd. for C₁₄H₁₅N₃O₄: 289; found:290 (M+H)⁺.

Step 2. Preparation of(S)-2-(methoxycarbonylamino)-3-(1H-pyrazol-1-yl)propanoic acid (Cap-129)

(S)-2-(benzyloxycarbonylamino)-3-(1H-pyrazol-1-yl)propanoic acid (0.20g, 0.70 mmol) was hydrogenated in the presence of Pd—C (45 mg) in MeOH(5 mL) at atmospheric pressure for 2 h. The product appeared to beinsoluble in MeOH, therefore the reaction mixture was diluted with 5 mLH₂O and a few drops of 6N Hcl. The homogeneous solution was filteredthrough diatomaceous earth (CELITE®), and the MeOH removed in vacuo. Theremaining solution was frozen and lyophyllized to give a yellow foam(188.9 mg). This material was suspended in THF—H₂O (1:1, 0 mL) and thencooled to 0° C. To the cold mixture was added NaHCO₃ (146.0 mg, 1.74mmol) carefully (evolution of CO₂). After gas evolution had ceased (ca.15 min) ClCO₂Me (0.06 mL, 0.78 mmol) was added dropwise. The mixture wasallowed to stir for 2 h and was acidified to pH˜2 with 6N HCl and pouredinto EtOAc. The layers were separated and the aqueous phase extractedwith EtOAC (×5). The combined organic layers were washed (brine), dried(Na₂SO₄), filtered, and concentrated to give the title compound as acolorless solid (117.8 mg, 79%). ¹H NMR (400 MHz, DMSO-d) δ 13.04 (s,1H), 7.63 (d, J=2.6 Hz, 1H), 7.48 (d, J=8.1 Hz, 1H), 7.44 (d, J=1.5 Hz,1H), 6.19 (app t, J=2.0 Hz, 1H), 4.47 (dd, J=3.0, 12.9 Hz, 1H),4.29-4.41 (m, 2H), 3.48 (s, 3H). LCMS: Anal. Calcd. for C₈H₁₁N₃O₄: 213;found: 214 (M+H)⁺.

Cap-130 was prepared by acylation of commercially available(R)-phenylglycine analogous to the procedure given in: Calmes, M.;Daunis, J.; Jacquier, R.; Verducci, J. Tetrahedron, 1987, 43(10), 2285.

Step a: Dimethylcarbamoyl chloride (0.92 mL, 10 mmol) was added slowlyto a solution of (S)-benzyl 2-amino-3-methylbutanoate hydrochloride(2.44 g; 10 mmol) and Hunig's base (3.67 mL, 21 mmol) in THF (50 mL).The resulting white suspension was stirred at room temperature overnight(16 hours) and concentrated under reduced pressure. The residue waspartitioned between ethyl acetate and water. The organic layer waswashed with brine, dried (MgSO₄), filtered, and concentrated underreduced pressure. The resulting yellow oil was purified by flashchromatography, eluting with ethyl acetate:hexanes (1:1). Collectedfractions were concentrated under vacuum providing 2.35 g (85%) of clearoil. ¹H NMR (300 MHz, DMSO-d₆) δ ppm 0.84 (d, J=6.95 Hz, 3H), 0.89 (d,J=6.59 Hz, 3H), 1.98-2.15 (m, 1H), 2.80 (s, 6H), 5.01-5.09 (m, J=12.44Hz, 1H), 5.13 (d, J=12.44 Hz, 1H), 6.22 (d, J=8.05 Hz, 1H), 7.26-7.42(m, 5H). LC (Cond. 1): RT=1.76 min; MS: Anal. Calcd. for [M+H]⁺C₁₆H₂₂N₂O₃: 279.17; found 279.03.

Step b: To a MeOH (50 mL) solution of the intermediate prepared above(2.35 g; 8.45 mmol) was added Pd/C (10%; 200 mg) and the resulting blacksuspension was flushed with N₂ (3×) and placed under 1 atm of H₂. Themixture was stirred at room temperature overnight and filtered though amicrofiber filter to remove the catalyst. The resulting clear solutionwas then concentrated under reduced pressure to obtain 1.43 g (89%) ofCap-131 as a white foam, which was used without further purification. ¹HNMR (500 MHz, DMSO-d₆) δ ppm 0.87 (d, J=4.27 Hz, 3H), 0.88 (d, J=3.97Hz, 3H), 1.93-2.11 (m, 1H), 2.80 (s, 6H), 3.90 (dd, J=8.39, 6.87 Hz,1H), 5.93 (d, J=8.54 Hz, 1H), 12.36 (s, 1H). LC (Cond. 1): RT=0.33 min;MS: Anal. Calcd. for [M+H]⁺ C₈H₁₇N₂O₃: 189.12; found 189.04.

Cap-132 was prepared from (S)-benzyl 2-aminopropanoate hydrochlorideaccording to the method described for Cap-131. ¹H NMR (500 MHz, DMSO-d₆)δ ppm 1.27 (d, J=7.32 Hz, 3H), 2.80 (s, 6H), 4.06 (qt, 1H), 6.36 (d,J=7.32 Hz, 1H), 12.27 (s, 1H). LC (Cond. 1): RT=0.15 min; MS: Anal.Calcd. for [M+H]⁺ C₆H₁₃N₂O₃: 161.09; found 161.00.

Cap-133 was prepared from (S)-tert-butyl 2-amino-3-methylbutanoatehydrochloride and 2-fluoroethyl chloroformate according to the methoddescribed for Cap-47. ¹H NMR (500 MHz, DMSO-d₆) δ ppm 0.87 (t, J=6.71Hz, 6H), 1.97-2.10 (m, 1H), 3.83 (dd, J=8.39, 5.95 Hz, 1H), 4.14-4.18(m, 1H), 4.20-4.25 (m, 1H), 4.50-4.54 (m, 1H), 4.59-4.65 (m, 1H), 7.51(d, J=8.54 Hz, 1H), 12.54 (s, 1H).

Cap-134 was prepared from (S)-diethyl alanine and methyl chloroformateaccording to the method described for Cap-5. ¹H NMR (500 MHz, DMSO-d₆) δppm 0.72-0.89 (m, 6H), 1.15-1.38 (m, 4H), 1.54-1.66 (m, 1H), 3.46-3.63(m, 3H), 4.09 (dd, J=8.85, 5.19 Hz, 1H), 7.24 (d, J=8.85 Hz, 1H), 12.55(s, 1H). LC (Cond. 2): RT=0.66 min; LC/MS: Anal. Calcd. for [M+H]⁺C₉H₁₈NO₄: 204.12; found 204.02.

A solution of D-2-amino-(4-fluorophenyl)acetic acid (338 mg, 2.00 mmol),1N HCl in diethylether (2.0 mL, 2.0 mmol) and formalin (37%, 1 mL) inmethanol (5 mL) was subjected to balloon hydrogenation over 11%palladium on carbon (60 mg) for 16 h at 25° C. The mixture was thenfiltered through Celite to afford the HCl salt of Cap-135 as a whitefoam (316 mg, 80%). ¹H NMR (300 MHz, MeOH-d₄) δ 7.59 (dd, J=8.80, 5.10Hz, 2H), 7.29 (t, J=8.6 Hz, 2H), 5.17 (s, 1H), 3.05 (v br s, 3H), 2.63(v br s, 3H); R_(t)=0.19 min (Cond.-MS-W5); 95% homogenity index; LRMS:Anal. Calcd. for [M+H]⁺ C₁₀H₃FNO₂: 198.09; found: 198.10.

To a cooled (−50° C.) suspension of 1-benzyl-1H-imidazole (1.58 g, 10.0mmol) in anhydrous diethyl ether (50 mL) under nitrogen was addedn-butyl lithium (2.5 M in hexanes, 4.0 mL, 10.0 mmol) dropwise. Afterbeing stirred for 20 min at −50° C., dry carbon dioxide (passed throughDrierite) was bubbled into the reaction mixture for 10 min before it wasallowed to warm up to 25° C. The heavy precipitate which formed onaddition of carbon dioxide to the reaction mixture was filtered to yielda hygroscopic, white solid which was taken up in water (7 mL), acidifiedto pH=3, cooled, and induced to crystallize with scratching. Filtrationof this precipitate gave a white solid which was suspended in methanol,treated with 1N HCl/diethyl ether (4 mL) and concentrated in vacuo.Lyophilization of the residue from water (5 mL) afforded the HCl salt ofCap-136 as a white solid (817 mg, 40%). ¹H NMR (300 MHz, DMSO-d₆) δ 7.94(d, J=1.5 Hz, 1H), 7.71 (d, J=1.5 Hz, 1H), 7.50-7.31 (m, 5H), 5.77 (s,2H); R_(t)=0.51 min (Cond.-MS-W5); 95% homogenity index; LRMS: Anal.Calc. for [M+H]⁺ C₁, H₁₂N₂O₂: 203.08; found: 203.11.

A suspension of 1-chloro-3-cyanoisoquinoline (188 mg, 1.00 mmol;prepared according to the procedure in WO 2003/099274) (188 mg, 1.00mmol), cesium fluoride (303.8 mg, 2.00 mmol),bis(tri-tert-butylphosphine)palladium dichloride (10 mg, 0.02 mmol) and2-(tributylstannyl)furan (378 μL, 1.20 mmol) in anhydrous dioxane (10mL) under nitrogen was heated at 80° C. for 16 h before it was cooled to25° C. and treated with saturated, aqueous potassium fluoride solutionwith vigorous stirring for 1 h. The mixture was partitioned betweenethyl acetate and water and the organic phase was separated, washed withbrine, dried over Na₂SO₄, filtered and concentrated. Purification of theresidue on silica gel (elution with 0% to 30% ethyl acetate/hexanes)afforded Cap-137, step a as a white solid which was used as is (230 mg,105%). R_(t)=1.95 min (Cond.-MS-W2); 90% homogeneity index; LRMS: Anal.Calc. for [M+H]⁺ C₁₄H₈N₂O: 221.07; found: 221.12.

To a suspension of Cap 137, step a, (110 mg, 0.50 mmol) and sodiumperiodate (438 mg, 2.05 mmol) in carbon tetrachloride (1 mL),acetonitrile (1 mL) and water (1.5 mL) was added ruthenium trichloridehydrate (2 mg, 0.011 mmol). The mixture was stirred at 25° C. for 2 hand then partitioned between dichloromethane and water. The aqueouslayer was separated, extracted twice more with dichloromethane and thecombined dichloromethane extracts were dried over Na₂SO₄, filtered andconcentrated. Trituration of the residue with hexanes afforded Cap-137(55 mg, 55%) as a grayish-colored solid. R_(t)=1.10 min (Cond.-MS-W2);90% homogeneity index; LCMS: Anal. Calc. for [M+H]⁺ C₁₁H₈N₂O₂: 200.08;found: 200.08.

Caps 138 to 158

To a stirred suspension of 5-hydroxisoquinoline (prepared according tothe procedure in WO 2003/099274) (2.0 g, 13.8 mmol) andtriphenylphosphine (4.3 g, 16.5 mmol) in dry tetrahydrofuran (20 mL) wasadded dry methanol (0.8 mL) and diethyl azodicarboxylate (3.0 mL, 16.5mmol) portionwise. The mixture was stirred at room temperature for 20 hbefore it was diluted with ethyl acetate and washed with brine, driedover Na₂SO₄, filtered and concentrated. The residue was preabsorbed ontosilica gel and purified (elution with 40% ethyl acetate/hexanes) toafford Cap-138, step a as a light yellow solid (1.00 g, 45%). ¹H NMR(CDCl₃, 500 MHz) δ 9.19 (s, 1H), 8.51 (d, J=6.0 Hz, 1H), 7.99 (d, J=6.0Hz, 1H), 7.52-7.50 (m, 2H), 7.00-6.99 (m, 1H), 4.01 (s, 3H); R_(t)=0.66min (Cond. D2); 95% homogeneity index; LCMS: Anal. Calc. for [M+H]⁺C₁₀H₁₀NO; 160.08; found 160.10.

To a stirred solution of Cap 138, step a (2.34 g, 14.7 mmol) inanhydrous dichloromethane (50 mL) at room temperature was addedmeta-chloroperbenzoic acid (77%, 3.42 g, 19.8 mmol) in one portion.After being stirred for 20 h, powdered potassium carbonate (2.0 g) wasadded and the mixture was stirred for 1 h at room temperature before itwas filtered and concentrated to afford Cap-138, step b as a pale,yellow solid which was sufficiently pure to carry forward (2.15 g,83.3%). ¹H NMR (CDCl₃, 400 MHz) δ 8.73 (d, J=1.5 Hz, 1H), 8.11 (dd,J=7.3, 1.7 Hz, 1H), 8.04 (d, J=7.1 Hz, 1H), 7.52 (t, J=8.1 Hz, 1H), 7.28(d, J=8.3 Hz, 1H), 6.91 (d, J=7.8 Hz, 1H), 4.00 (s, 3H); R_(t) 0.92 min,(Cond.-D1); 90% homogenity index; LCMS: Anal. Calc. for [M+H]⁺ C₁₀H₁₀NO:176.07; found: 176.0.

To a stirred solution of Cap 138, step b (0.70 g, 4.00 mmol) andtriethylamine (1.1 mL, 8.00 mmol) in dry acetonitrile (20 mL) at roomtemperature under nitrogen was added trimethylsilylcyanide (1.60 mL,12.00 mmol). The mixture was heated at 75° C. for 20 h before it wascooled to room temperature, diluted with ethyl acetate and washed withsaturated sodium bicarbonate solution and brine prior to drying overNa₂SO₄ and solvent concentration. The residue was flash chromatographedon silica gel (elution with 5% ethyl acetate/hexanes) to 25% ethylacetate/hexanes to afford Cap-138, step c (498.7 mg) as a white,crystalline solid along with 223 mg of additional Cap-138, step crecovered from the filtrate. ¹H NMR (CDCl₃, 500 MHz) δ 8.63 (d, J=5.5Hz, 1H), 8.26 (d, J=5.5 Hz, 1H), 7.88 (d, J=8.5 Hz, 1H), 7.69 (t, J=8.0Hz, 1H), 7.08 (d, J=7.5 Hz, 1H), 4.04 (s, 3H); R_(t)=1.75 min,(Cond.-D1); 90% homogeneity index; LCMS: Anal. Calc. for [M+H]⁺ C₁H₉N₂O:185.07; found: 185.10.

Cap-138, step c (0.45 g, 2.44 mmol) was treated with 5N sodium hydroxidesolution (10 mL) and the resulting suspension was heated at 85° C. for 4h, cooled to 25° C., diluted with dichloromethane and acidified with 1Nhydrochloric acid. The organic phase was separated, washed with brine,dried over Na₂SO₄, concentrated to ¼ volume and filtered to affordCap-138 as a yellow solid (0.44 g, 88.9%). ¹H NMR (DMSO-d₆, 400 MHz) δ13.6 (br s, 1H), 8.56 (d, J=6.0 Hz, 1H), 8.16 (d, J=6.0 Hz, 1H), 8.06(d, J=8.8 Hz, 1H), 7.71-7.67 (m, 1H), 7.30 (d, J=8.0 Hz, 1H), 4.02 (s,3H); R_(t)=0.70 min (Cond.-D1); 95% homogenity index; LCMS: Anal. Calc.for [M+H]⁺ C₁₁H₁₀NO₃: 204.07; found: 204.05.

To a thick-walled, screw-top vial containing an argon-degassedsuspension of 1-chloro-6-methoxyisoquinoline (1.2 g, 6.2 mmol; preparedaccording to the procedure in WO 2003/099274), potassium cyanide (0.40g, 6.2 mmol), 1,5-bis(diphenylphosphino)pentane (0.27 g, 0.62 mmol) andpalladium (II) acetate (70 mg, 0.31 mmol) in anhydrous toluene (6 mL)was added N,N,N′,N′-tetramethylethylenediamine (0.29 mL, 2.48 mmol). Thevial was sealed, heated at 150° C. for 22 h and then allowed to cool to25° C. The reaction mixture was diluted with ethyl acetate, washed withwater and brine, dried over Na₂SO₄, filtered and concentrated. Theresidue was purified on silica gel eluting with 5% ethyl acetate/hexanesto 25% ethyl acetate/hexanes to afford Cap-39, step a as a white solid(669.7 mg). ¹H NMR (CDCl₃, 500 MHz) δ 8.54 (d, J=6.0 Hz, 1H), 8.22 (d,J=9.0 Hz, 1H), 7.76 (d, J=5.5 Hz, 1H), 7.41-7.39 (m, 1H), 7.13 (d, J=2.0Hz, 1H), 3.98 (s, 3H); R_(t)=1.66 min (Cond.-D1); 90% homogenity index;LCMS: Anal. Calc. for [M+H]⁺ C₁₁H₉N₂O: 185.07; found: 185.20.

Cap-139 was prepared from the basic hydrolysis of Cap-139, step a with5N NaOH according to the procedure described for Cap 138. ¹H NMR (400MHz, DMSO-d₆) δ 13.63 (v br s, 1H), 8.60 (d, J=9.3 Hz, 1H), 8.45 (d,J=5.6 Hz, 1H), 7.95 (d, J=5.9 Hz, 1H), 7.49 (d, J=2.2 Hz, 1H), 7.44 (dd,J=9.3, 2.5 Hz, 1H), 3.95 (s, 3H); R_(t)=0.64 min (Cond.-D1); 90%homogenity index; LCMS: Anal. Calc. for [M+H]⁺ C₁₁H₁₀NO₃: 204.07; found:204.05.

To a vigorously-stirred mixture of 1,3-dichloro-5-ethoxyisoquinoline(482 mg, 2.00 mmol; prepared according to the procedure in WO2005/051410), palladium (II) acetate (9 mg, 0.04 mmol), sodium carbonate(223 mg, 2.10 mmol) and 1,5-bis(diphenylphosphino)pentane (35 mg, 0.08mmol) in dry dimethylacetamide (2 mL) at 25° C. under nitrogen was addedN,N,N′,N′-tetramethylethylenediamine (60 mL, 0.40 mmol). After 10 min,the mixture was heated to 150° C., and then a stock solution of acetonecyanohydrin (prepared from 457 μL of acetone cyanohydrin in 4.34 mL DMA)was added in 1 mL portions over 18 h using a syringe pump. The mixturewas then partitioned between ethyl acetate and water and the organiclayer was separated, washed with brine, dried over Na₂SO₄, filtered andconcentrated. The residue was purified on silica gel eluting with 10%ethyl acetate/hexanes to 40% ethyl acetate/hexanes to afford Cap-140,step a as a yellow solid (160 mg, 34%). R_(t)=2.46 min (Cond.-MS-W2);90% homogenity index; LCMS: Anal. Calc. for [M+H]⁺ C₁₂H₉ClN₂O: 233.05;found: 233.08.

Cap-140 was prepared by the acid hydrolysis of Cap-140, step a with 12NHCl as described in the procedure for the preparation of Cap 141,described below. R_(t)=2.24 min (Cond.-MS-W2); 90% homogenity index;LCMS: Anal. Calc. for [M+H]⁺ C₁₂H₁₁ClNO₃: 252.04; found: 252.02.

Cap-141, step a was prepared from 1-bromo-3-fluoroisoquinoline (preparedfrom 3-amino-1-bromoisoquinoline using the procedure outlined in J. Med.Chem. 1970, 13, 613) as described in the procedure for the preparationof Cap-140, step a (vide supra). ¹H NMR (500 MHz, CDCl₃) δ 8.35 (d,J=8.5 Hz, 1H), 7.93 (d, J=8.5 Hz, 1H), 7.83 (t, J=7.63 Hz, 1H),7.77-7.73 (m, 1H), 7.55 (s, 1H); R_(t)=1.60 min (Cond.-D1); 90%homogenity index; LCMS: Anal. Calc for [M+H]⁺ C₁₀H₆FN₂: 173.05; found:172.99.

Cap-141, step a (83 mg, 0.48 mmol) was treated with 12N HCl (3 mL) andthe resulting slurry was heated at 80° C. for 16 h before it was cooledto room temperature and diluted with water (3 mL). The mixture wasstirred for 10 min and then filtered to afford Cap-141 as an off-whitesolid (44.1 mg, 47.8%). The filtrate was diluted with dichloromethaneand washed with brine, dried over Na₂SO₄, and concentrated to affordadditional Cap-141 which was sufficiently pure to be carried forwarddirectly (29.30 mg, 31.8%). ¹H NMR (DMSO-d₆, 500 MHz) δ 14.0 (br s, 1H),8.59-8.57 (m, 1H), 8.10 (d, J=8.5 Hz, 1H), 7.88-7.85 (m, 2H), 7.74-7.71(m, 1H); R_(t)=1.33 min (Cond.-D1); 90% homogenity index; LCMS: AnalCalc. for [M+H]⁺ C₁₀H₇FNO₂: 192.05; found: 191.97.

Cap-142, step a was prepared from 4-bromoisoquinoline N-oxide asdescribed in the two-step procedure for the preparation of Cap-138,steps b and c. R_(t)=1.45 min (Cond.-MS-W1); 90% homogenity index; LCMS:Anal. Calc. for [M+H]⁺ C₁₀H₆BrN₂: 232.97; found: 233.00.

To an argon-degassed suspension of Cap-142, step a (16 mg, 0.50 mmol),potassium phosphate tribasic (170 mg, 0.80 mmol), palladium (11) acetate(3.4 mg, 0.015 mmol) and 2-(dicyclohexylphosphino)biphenyl (11 mg, 0.03mmol) in anhydrous toluene (1 mL) was added morpholine (61 μL, 0.70mmol). The mixture was heated at 100° C. for 16 h, cooled to 25° C. andfiltered through diatomaceous earth (CELITE®). Purification of theresidue on silica gel, eluting with 10% to 70% ethyl acetate/hexanesafforded Cap-142, step b (38 mg, 32%) as a yellow solid, which wascarried forward directly. R_(t)=1.26 min (Cond.-MS-W1); 90% homogenityindex; LCMS. Anal. Calc. for [M+H]⁺ C₁₄N₃O: 240.11; found: 240.13.

Cap-142 was prepared from Cap-142, step b with 5N sodium hydroxide asdescribed in the procedure for Cap 138. R_(t)=0.72 min (Cond.-MS-W1);90% homogenity index; LCMS: Anal. Calc. for [M+]⁺ C₁₄H₁₅N₂O₃: 259.11;found: 259.08.

To a stirred solution of 3-amino-1-bromoisoquinoline (444 mg, 2.00 mmol)in anhydrous dimethylformamide (10 mL) was added sodium hydride (60%,unwashed, 96 mg, 2.4 mmol) in one portion. The mixture was stirred at25° C. for 5 min before 2-bromoethyl ether (90%, 250 μL, 2.00 mmol) wasadded. The mixture was stirred further at 25° C. for 5 h and at 75° C.for 72 h before it was cooled to 25° C., quenched with saturatedammonium chloride solution and diluted with ethyl acetate. The organiclayer was separated, washed with water and brine, dried over Na₂SO₄,filtered and concentrated. Purification of the residue on silica geleluting with 0% to 70% ethyl acetate/hexanes afforded Cap-143, step a asa yellow solid (180 mg, 31%). R_(t)=1.75 min (Cond.-MS-WI); 90%homogenity index; LCMS: Anal. Calc. for [M+H]⁺ C₁₃H₄BrN₂O: 293.03;found: 293.04.

To a cold (−60° C.) solution of Cap-143, step a (154 mg, 0.527 mmol) inanhydrous tetrahydrofuran (5 mL) was added a solution of n-butyllithiumin hexanes (2.5 M, 0.25 mL, 0.633 mmol). After 10 min, dry carbondioxide was bubbled into the reaction mixture for 10 min before it wasquenched with 1N HCl and allowed to warm to 25° C. The mixture was thenextracted with dichloromethane (3×30 mL) and the combined organicextracts were concentrated in vacuo. Purification of the residue by areverse phase HPLC (MeOH/water/TFA) afforded Cap-143 (16 mg, 12%).R_(t)=1.10 min (Cond.-MS-WI); 90% homogenity index; LCMS: Anal. Calc.for [M+H]⁺ C₁₄H₁₅N₂O₃: 259.11; found: 259.08.

1,3-Dichloroisoquinoline (2.75 g, 13.89 mmol) was added in smallportions to a cold (0° C.) solution of fuming nitric acid (10 mL) andconcentrated sulfuric acid (10 mL). The mixture was stirred at 0° C. for0.5 h before it was gradually warmed to 25° C. where it stirred for 16h. The mixture was then poured into a beaker containing chopped ice andwater and the resulting suspension was stirred for 1 h at 0° C. beforeit was filtered to afford Cap-144, step a (2.73 g, 81%) as a yellowsolid which was used directly. R_(t)=2.01 min. (Cond.-D1); 95%homogenity index; LCMS: Anal. Calc. for [M+H]⁺ C₉H₅Cl₂N₂O₂: 242.97;found: 242.92.

Cap-144, step a (0.30 g, 1.23 mmol) was taken up in methanol (60 mL) andtreated with platinum oxide (30 mg), and the suspension was subjected toParr hydrogenation at 7 psi H₂ for 1.5 h. Then formalin (5 mL) andadditional platinum oxide (30 mg) were added, and the suspension wasresubjected to Parr hydrogenation at 45 psi H₂ for 13 h. It was thensuction-filtered through diatomaceous earth (CELITE®) and concentrateddown to ¼ volume. Suction-filtration of the ensuing precipitate affordedthe title compound as a yellow solid which was flash chromatographed onsilica gel eluting with 5% ethyl acetate in hexanes to 25% ethyl acetatein hexanes to afford Cap-144, step b (231 mg, 78%) as a pale yellowsolid. R_(t) 2.36 min (Cond.-D1); 95% homogenity index; ¹H NMR (400 MHz,CDCl₃) δ 8.02 (s, 1H), 7.95 (d, J=8.6 Hz, 1H), 7.57-7.53 (m, 1H), 7.30(d, J=7.3 Hz, 1H), 2.88 (s, 6H); LCMS: Anal. Calc. for [M+H]⁺C₁₁H₁₁Cl₂N₂: 241.03; found: 241.02.

HRMS: Anal. Calc. for [M+H]⁺ C₁₁H₁₁Cl₂N₂: 241.0299; found: 241.0296.

Cap-144, step c was prepared from Cap-144, step b according to theprocedure described for the preparation of Cap-139, step a. R_(t)=2.19min (Cond.-D1); 95% homogenity index; LCMS: Anal. Calc. for [M+H]⁺C₁₂H₁₁ClN₃: 232.06; found: 232.03. HRMS: Anal. Calc. for [M+H]⁺C₁₂H₁₁ClN₃: 232.0642; found: 232.0631.

Cap-144 was prepared according to the procedure described for Cap-141.R_(t)=2.36 min (Cond.-D1); 90%; LCMS: Anal. Calc. for [M+H]⁺C₁₂H₁₂ClN₂O₂: 238.01; found: 238.09.

Caps-145 to 162

Caps-145 to 162 were prepared from the appropriate 1-chloroisoquinolinesaccording to the procedure described for the preparation of Cap-138(Method A) or Cap-139 (Method B) unless noted otherwise as outlinedbelow.

R_(t) (LC-Cond.); % homogeneity index; Cap # Cap Method Hydrolysis MSdata Cap-145

B 12N HCl 1.14 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇ClNO₂: 208.02; found: 208.00. Cap-146

A 5N NaOH 1.40 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₁₀NO₃: 204.07; found: 204.06. Cap-147

B 5N NaOH 0.87 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₁₀NO₃: 204.07; found: 204.05. Cap-148

A 5N NaOH 0.70 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₁₀NO₃: 204.07; found: 204.05. Cap-149

A 5N NaOH 0.70 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₁₀NO₃: 204.07; found: 204.05. Cap-150

A 12N HCl 0.26 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₁₀NO₃: 204.07; found: 204.04. Cap-151

B 12N HCl 1.78 min (Cond.-D1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₉ClNO₃: 238.03; found: 238.09. Cap-152

B 12N HCl 1.65 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₁H₉ClNO₃: 238.00; found: 238.09. Cap-153

A 6N HCl 1.18 min (Cond.-MS-W1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇BrNO₂: 251.97; found: 251.95. Cap-154

B 5N NaOH 0.28 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇FNO₂: 192.05; found: 192.03. Cap-155

B 5N NaOH 0.59 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇ClNO₂: 208.02; found: 208.00. Cap-156

B 5N NaOH 0.60 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇ClNO₂: 208.02; found: 208.03. Cap-157

B 12N HCl 1.49 min (Cond.-D1); 95%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₁₇ClNO: 208.02; found: 208.00. Cap-158

B 5N NaOH 0.69 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇ClNO₂: 208.02; found: 208.01. Cap-159

B 5N NaOH 0.41 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇FNO₂: 192.05; found: 192.03. Cap-160

B 5N NaOH 0.30 min (Cond.-MS-W1); 90%; LCMS: Anal. Calc. for [M + H]⁺C₁₀H₇FNO₂: 192.05; found: 192.03. Cap-161

— — 0.70 min (Cond. D1); 95%; LCMS: Anal. Calc. for [M + H]⁺ C₁₂H₁₃N₂O₂:217.10; found: 217.06. Cap-162

— — 0.65 min (Cond.-M3); 95%; LCMS: Anal. Calc. for [M + H]⁺ C₁₁H₁₀NO₃:204.07; found: 203.94.

To a solution of 2-ketobutyric acid (1.0 g, 9.8 mmol) in diethylether(25 ml) was added phenylmagnesium bromide (22 ml, 1M in THF) dropwise.The reaction was stirred at 25° C. under nitrogen for 17.5 h. Thereaction was acidified with 1N HCl and the product was extracted withethyl acetate (3×100 ml). The combined organic layer was washed withwater followed by brine and dried over MgSO₄. After concentration invacuo, a white solid was obtained. The solid was recrystallized fromhexanes/ethyl acetate to afford Cap-163 as white needles (883.5 mg). ¹HNMR (DMSO-d₆, δ=2.5 ppm, 500 MHz): 12.71 (br s, 1H), 7.54-7.52 (m, 2H),7.34-7.31 (m, 2H), 7.26-7.23 (m, 1H), 5.52-5.39 (br s, 1H), 2.11 (m,1H), 1.88 (m, 1H), 0.79 (app t, J=7.4 Hz, 3H).

A mixture of 2-amino-2-phenylbutyric acid (1.5 g, 8.4 mmol),formaldehyde (14 mL, 37% in water), 1N HCl (10 mL) and 10% Pd/C (0.5 mg)in MeOH (40 mL) was exposed to H₂ at 50 psi in a Parr bottle for 42 h.The reaction was filtered over Celite and concentrated in vacuo, theresidue was taken up in MeOH (36 mL) and the product was purified with areverse phase HPLC (MeOH/H₂O/TFA) to afford the TFA salt of Cap-164 as awhite solid (1.7 g). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 500 MHz) 7.54-7.47 (m,5H), 2.63 (m, 1H), 2.55 (s, 6H), 2.31 (m, 1H), 0.95 (app t, J=7.3 Hz,3H).

To a mixture of 2-amino-2-indanecarboxylc acid (258.6 mg, 1.46 mmol) andformic acid (0.6 ml, 15.9 mmol) in 1,2-dichloroethane (7 ml) was addedformaldehyde (0.6 ml, 37% in water). The mixture was stirred at 25° C.for 15 min then heated at 70° C. for 8 h. The volatile component wasremoved in vacuo, and the residue was dissolved in DMF (14 mL) andpurified by a reverse phase HPLC (MeOH/H₂O/TFA) to afford the TFA saltof Cap-165 as a viscous oil (120.2 mg). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 500MHz): 7.29-7.21 (m, 4H), 3.61 (d, J=17.4 Hz, 2H), 3.50 (d, J=17.4 Hz,2H), 2.75 (s, 6H). LC/MS: Anal. Calcd. for [M+H]⁺ Cl₂H₁₆NO₂; 206.12;found: 206.07.

Caps-166a and -166b were prepared from(1S,4S)-(+)-2-methyl-2,5-diazabicyclo[2.2.1]heptane (2 HBr) according tothe method described for the synthesis of Cap-7a and Cap-7b, with theexception that the benzyl ester intermediate was separated using asemi-prep Chirialcel OJ column, 20×250 mm, 10 μm eluting with 85:15heptane/ethanol mixture at 10 mL/min elution rate for 25 min. Cap-166b:¹H NMR (DMSO-d₆, δ=2.5 ppm, 500 MHz): 7.45 (d, J=7.3 Hz, 2H), 7.27-7.19(m, 3H), 4.09 (s, 1H), 3.34 (app br s, 1H), 3.16 (app br s, 1H), 2.83(d, J=10.1 Hz, 1H), 2.71 (m, 2H), 2.46 (m, 1H), 2.27 (s, 3H), 1.77 (d,J=9.8 Hz, 1H), 1.63 (d, J=9.8 Hz, 1H). LC/MS: Anal. Calcd. for [M+H]⁺C₁₄H₁₉N₂O₂: 247.14; found: 247.11.

A solution of racemic Boc-1,3-dihydro-2H-isoindole carboxylic acid (1.0g, 3.8 mmol) in 20% TFA/CH₂Cl₂ was stirred at 25° C. for 4 h. All thevolatile component was removed in vacuo. A mixture of the resultantcrude material, formaldehyde (15 mL, 37% in water), 1N HCl (10 mL) and10% Pd/C (10 mg) in MeOH was exposed to H₂ (40 PSI) in a Parr bottle for23 h. The reaction mixture was filtered over Celite and concentrated invacuo to afford Cap-167 as a yellow foam (873.5 mg). ¹H NMR (DMSO-d₆,δ=2.5 ppm, 500 MHz) 7.59-7.38 (m, 4H), 5.59 (s, 1H), 4.84 (d, J=14 Hz,1H), 4.50 (d, J=14.1 Hz, 1H), 3.07 (s, 3H). LC/MS: Anal. Calcd. for[M+H]⁺ C₁₀H₁₂NO₂: 178.09; found: 178.65.

Racemic Cap-168 was prepared from racemic Boc-aminoindane-1-carboxylicacid according to the procedure described for the preparation ofCap-167. The crude material was employed as such.

A mixture of 2-amino-2-phenylpropanoic acid hydrochloride (5.0 g, 2.5mmol), formaldehyde (15 ml, 37% in water), 1N HCl (15 ml), and 10% Pd/C(1.32 g) in MeOH (60 mL) was placed in a Parr bottle and shaken underhydrogen (55 PSI) for 4 days. The reaction mixture was filtered overCelite and concentrated in vacuo. The residue was taken up in MeOH andpurified by reverse phase prep-HPLC (MeOH/water/TFA) to afford the TFAsalt of Cap-169 as a viscous semi-solid (2.1 g). ¹H NMR (CDCl₃, δ=7.26ppm, 500 MHz): 7.58-7.52 (m, 2H), 7.39-7.33 (m, 3H), 2.86 (br s, 3H),2.47 (br s, 3H), 1.93 (s, 3H). LC/MS: Anal. Calcd. for [M+H]⁺ C₁₁H₁₆NO₂:194.12; found: 194.12.

To (S)-2-amino-2-(tetrahydro-2H-pyran-4-yl)acetic acid (505 mg; 3.18mmol; obtained from Astatech) in water (15 ml) was added sodiumcarbonate (673 mg; 6.35 mmol), and the resultant mixture was cooled to0° C. and then methyl chloroformate (0.26 ml; 3.33 mmol) was addeddropwise over 5 minutes. The reaction was allowed to stir for 18 hourswhile allowing the bath to thaw to ambient temperature. The reactionmixture was then partitioned between 1N HCl and ethyl acetate. Theorganic layer was removed and the aqueous layer was further extractedwith 2 additional portions of ethyl acetate. The combined organic layerswere washed with brine, dried over magnesium sulfate, filtered andconcentrated in vacuo to afford Cap-170 a colorless residue. ¹H NMR (500MHz, DMSO-d₆ 6 ppm 12.65 (1H, br s), 7.44 (1H, d, J=8.24 Hz), 3.77-3.95(3H, m), 3.54 (3H, s), 3.11-3.26 (2H, m), 1.82-1.95 (1H, m), 1.41-1.55(2H, m), 1.21-1.39 (2H, m); LC/MS: Anal. Calcd. for [M+H]⁺ C₉H₁₆NO₅:218.1; found 218.1.

A solution of methyl2-(benzyloxycarbonylamino)-2-(oxetan-3-ylidene)acetate (200 mg, 0.721mmol; Il Farmaco (2001), 56, 609-613) in ethyl acetate (7 ml) and CH₂Cl₂(4.00 ml) was degassed by bubbling nitrogen for 10 min. Dimethyldicarbonate (0.116 ml, 1.082 mmol) and Pd/C (20 mg, 0.019 mmol) werethen added, the reaction mixture was fitted with a hydrogen balloon andallowed to stir at ambient temperature overnight at which time TLC (95:5CH₂Cl₂/MeOH: visualized with stain made from 1 g Ce(NH₄)₂SO₄, 6 gammonium molybdate, 6 ml sulfuric acid, and 100 ml water) indicatedcomplete conversion. The reaction was filtered through celite andconcentrated. The residue was purified via BIOTAGE® (load withdichloromethane on 25 samplet; elute on 25S column with dichloromethanefor 3CV then 0 to 5% MeOH/dichloromethane over 250 ml then hold at 5%MeOH/dichloromethane for 250 ml; 9 ml fractions). Collected fractionscontaining desired material and concentrated to 120 mg (81%) of methyl2-(methoxycarbonylamino)-2-(oxetan-3-yl)acetate as a colorless oil. ¹HNMR (500 MHz, CHLOROFORM-D) δ ppm 3.29-3.40 (m, J=6.71 Hz, 1H) 3.70 (s,3H) 3.74 (s, 3H) 4.55 (t, J=6.41 Hz, 1H) 4.58-4.68 (m, 2H) 4.67-4.78 (m,2H) 5.31 (br s, 1H). LC/MS: Anal. Calcd. for [M+H]⁺ C₈H₁₄NO₅: 204.2;found 204.0.

To methyl 2-(methoxycarbonylamino)-2-(oxetan-3-yl)acetate (50 mg, 0.246mmol) in THF (2 mL) and water (0.5 mL) was added lithium hydroxidemonohydrate (10.33 mg, 0.246 mmol). The resultant solution was allowedto stir overnight at ambient temperature. TLC (1:1 EA/Hex; Hanessianstain [1 g Ce(NH₄)₂SO₄, 6 g ammonium molybdate, 6 ml sulfuric acid, and100 ml water]) indicated ˜10% starting material remaining. Added anadditional 3 mg LiOH and allowed to stir overnight at which time TLCshowed no starting material remaining. Concentrated in vacuo and placedon high vac overnight providing 55 mg lithium2-(methoxycarbonylamino)-2-(oxetan-3-yl)acetate as a colorless solid. ¹HNMR (500 MHz, MeOD) δ ppm 3.39-3.47 (m, 1H) 3.67 (s, 3H) 4.28 (d, J=7.93Hz, 1H) 4.64 (t, J=6.26 Hz, 1H) 4.68 (t, J=7.02 Hz, 1H) 4.73 (d, J=7.63Hz, 2H).

EXAMPLES

The present disclosure will now be described in connection with certainembodiments which are not intended to limit its scope. On the contrary,the present disclosure covers all alternatives, modifications, andequivalents as can be included within the scope of the claims. Thus, thefollowing examples, which include specific embodiments, will illustrateone practice of the present disclosure, it being understood that theexamples are for the purposes of illustration of certain embodiments andare presented to provide what is believed to be the most useful andreadily understood description of its procedures and conceptual aspects.

Solution percentages express a weight to volume relationship, andsolution ratios express a volume to volume relationship, unless statedotherwise. Nuclear magnetic resonance (NMR) spectra were recorded eitheron a Bruker 300, 400, or 500 MHz spectrometer; the chemical shifts (δ)are reported in parts per million. Flash chromatography was carried outon silica gel (SiO₂) according to Still's flash chromatography technique(J. Org. Chem. 1978, 43, 2923).

Purity assessment and low resolution mass analysis were conducted on aShimadzu LC system coupled with Waters Micromass ZQ MS system. It shouldbe noted that retention times may vary slightly between machines.Compound retention time was determined according to the following LC/MScondition (noted as Cond. I), unless stated otherwise:

Column: Phenomenex-Luna 4.6×50 mm S10

Start % B=0

Final % B=100

Gradient Time=4 min

Flow Rate=4 mL/min

Wavelength=220

Solvent A=10% CH₃OH—90% H₂O—0.1% TFA

Solvent B=90% CH₃OH—10% H₂O—0.1% TFA

Example 1

Example 1, Step a

Diisopropylethylamine (0.8 mL, 4.59 mmol) was added dropwise to aheterogeneous mixture of 6-bromo-4-chloroquinazoline (0.979 g, 4.02mmol) and 4-(N-morpholino)aniline (0.783 g, 4.39 mmol) in CH₃CN (15 mL),and refluxed for 25.4 hours. The mixture was removed from the heatingbath and allowed to stand at room temperature for 16.5 hours. Theprecipitate was filtered, washed with CH₃CN and dried in vacuo to affordbromide 1a as light-green powder (1.336 g). 1 NMR (DMSO-d₆, δ=2.50, 400MHz): 9.76 (s, 1H), 8.83 (d, J=2.3, 1H), 8.54 (s, 1H), 7.95 (dd, J=8.9,2.1, 11H), 7.69 (d, J=8.8, 1H), 7.65 (d, J=9.1, 2H), 6.99 (d, S=9.1,2H), 3.75 (m, 4H), 3.10 (m, 4H). LC/MS: Anal. Calcd. for [M+H]⁺C₁₈H₁₈BrN₄O: 385.07; found 385.01.

Example 1, Step b

Diisopropylethylamine (18 mL, 103.3 mmol) was added dropwise, over 15minutes, to a heterogeneous mixture of N-Boc-L-proline (7.139 g, 33.17mmol), HATU (13.324 g, 35.04 mmol), the HCl salt of2-amino-1-(4-bromophenyl)ethanone (8.127 g, 32.44 mmol) in DMF (105 mL),and stirred at ambient condition for 55 minutes. Most of the volatilecomponent was removed in vacuo, and the resulting residue waspartitioned between ethyl acetate (300 mL) and water (200 mL). Theorganic layer was washed with water (200 mL) and brine, dried (MgSO₄),filtered, and concentrated in vacuo. A silica gel mesh was prepared fromthe residue and submitted to flash chromatography (silica gel, 50-60%ethyl acetate/hexanes) to provide ketoamide 1b as a white solid (12.8g). ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): 8.25-8.14 (m, 1H), 7.92 (br d,J=8.0, 2H), 7.75 (br d, J=8.6, 2H), 4.61 (dd, J=18.3, 5.7, 1H), 4.53(dd, J=18.1, 5.6, 1H), 4.22-4.12 (m, 1H), 3.43-3.35 (m, 1H), 3.30-3.23(m, 1H), 2.18-2.20 (m, 1H), 1.90-1.70 (m, 3H), 1.40/1.34 (two app br s,9H). LC (Cond. I): RT=1.70 min; LC/MS: Anal. Calcd. for [M+Na]⁺C₁₈H₂₃BrN₂NaO₄: 433.07; found 433.09.

Example 1, Step c

A mixture of ketoamide 1b (12.8 g, 31.12 mmol) and NH₄OAc (12.0 g, 155.7mmol) in xylenes (155 mL) was heated in a sealed tube at 140° C. for 2hours. The volatile component was removed in vacuo, and the residue waspartitioned carefully between ethyl acetate and water, whereby enoughsaturated NaHCO₃ solution was added so as to make the pH of the aqueousphase slightly basic after the shaking of the biphasic system. Thelayers were separated, and the aqueous layer was extracted with anadditional ethyl acetate. The combined organic phase was washed withbrine, dried (MgSO₄), filtered, and concentrated in vacuo. The resultingmaterial was recrystallized from ethyl acetate/hexanes to provide twocrops of imidazole 1c as a light-yellow dense solid, weighing 5.85 g.The mother liquor was concentrated in vacuo and submitted to a flashchromatography (silica gel; 30% ethyl acetate/hexanes) to provide anadditional 2.23 g of imidazole 1c. ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz):12.17/11.92/11.86 (m, 1H), 7.72-7.46/7.28 (m, 5H), 4.86-4.70 (m, 1H),3.52 (app br s, 1H), 3.36 (m, 1H), 2.30-1.75 (m, 4H), 1.40/1.15 (app brs, 9H). LC (Cond. I): RT=1.71 min; >98% homogeneity index; LC/MS: Anal.Calcd. for [M+H]⁺ C₁₈H₂₃BrN₃O₂: 392.10; found 391.96; HRMS: Anal. Calcd.for [M+H]⁺ C₁₈H₂₃BrN₃O₂: 392.0974; found 392.0959.

The optical purity of the two samples of 1c was assessed using thechiral HPLC conditions noted below:

Column: Chiralpak AD, 10 um, 4.6×50 mm

Solvent: 2% ethanol/heptane (isocratic)

Flow rate: 1 mL/min

Wavelength: either 220 or 254 nm

Relative retention time: 2.83 minutes (R), 5.34 minutes (S)

Result: ee>99% for the combined crops; ee=96.7% for the sample fromflash chromatography

Example 1, Step d

Pd(Ph₃P)₄ (469 mg, 0.406 mmol) was added to a pressure tube containing amixture of bromide 1c (4.008 g, 10.22 mmol), bis(pinacolato)diboron(5.422 g, 21.35 mmol), potassium acetate (2.573 g, 26.21 mmol) and1,4-dioxane (80 mL). The reaction flask was purged with nitrogen, cappedand heated with an oil bath at 80° C. for 16.5 hours. The reactionmixture was filtered and the filtrate was concentrated in vacuo. Theresulting crude material was partitioned carefully between CH₂Cl₂ (150mL) and an aqueous medium (50 mL water+10 mL saturated NaHCO₃ solution).The aqueous layer was extracted with CH₂Cl₂, and the combined organicphase was dried (MgSO₄), filtered, and concentrated in vacuo. Theresulting material was purified with flash chromatography (sample wasloaded with eluting solvent; 20-35% ethyl acetate/CH₂Cl₂) to provideboronate 1d, contaminated with pinacol, as an off-white dense solid; therelative mole ratio of 1d to pinacol was about 10:1 (¹H NMR). The sampleweighed 3.925 g after 2.5 days exposure to high vacuum. ¹H NMR (DMSO-d₆,δ=2.5 ppm, 400 MHz): 12.22/11.94/11.87 (m, 1H), 7.79-7.50/7.34-7.27 (m,5H), 4.86-4.70 (m, 1H), 3.52 (app br s, 1H), 3.36 (m, 1H), 2.27-1.77 (m,4H), 1.45-1.10 (m, 21H). LC (Cond. I): RT=1.64 min; LC/MS: Anal. Calcd.for [M+H]⁺ C₂₄H₃₅BN₃O₄: 440.27; found 440.23.

Example 1, Step e

Pd(Ph₃P)₄ (39.4 mg, 0.034 mmol) was added to a mixture of bromide 1a(387.2 mg, 1.005 mmol), boronate 1d (440.8 mg, 1.00 mmol), and NaHCO₃(273 mg, 3.25 mmol) in 1,2-dimethoxyethane (9 mL) and water (3 mL).Nitrogen was bubbled through the mixture for 2 minutes, and then it washeated with an oil bath at 80° C. until the reaction was complete asdetermined by LC/MS analysis. The reaction mixture was cooled to roomtemperature, and the volatile component was removed in vacuo. Theresidue was partitioned between CH₂Cl₂ and water, and the organic phasewas dried (MgSO₄), filtered, and concentrated in vacuo. The resultantmaterial was submitted to BIOTAGE® purification (100 g silica gel; 0-8%CH₃OH/EtOAc) to afford I e as yellow semi-foamy solid, containingresidual EtOAc and weighing 509 mg. ¹H NMR (DMSO-d₆, δ=2.5 ppm, 400MHz): 12.25 (br s, 0.17H), 11.96 (br s, 0.48H), 11.89 (br s, 0.35H),9.84 (app br s, 1H), 8.82 (br m, 1H), 8.50 (m, 2H), 8.23-8.18 (m, 1H),7.95-7.80 (m, 5H), 7.66 (d, J=8.9, 2H), 7.61-7.58 (br m, 0.82H), 7.37(br m, 0.18H), 7.01 (d, J=9, 2H), 4.88-4.78 (m, 1H), 3.76 (m, 4H), 3.55(m, 1H), 3.41-3.35 (m, 1H), 3.12 (m, 4H), 2.31-2.13 (m, 1H), 2.08-1.81(m, 3H), 1.41 (app br s, 3.75H), 1.17 (app br s, 5.25). LC (Cond. 1):RT=1.35 min; >95% homogeneity index. LC/MS: Anal. Calcd. for [M+H]⁺C₃₆H₄₀N₇O₃: 618.32; found 618.24.

Example 1, Step f

25% TFA/CH₂Cl₂ (8.0 mL) was added to carbamate 1e (474 mg, 0.768 mmol),and the resultant solution was stirred at ambient condition for 8 hours.The volatile component was removed in vacuo and the residue wasfree-based with MCX (6 g; CH₃OH wash; 2.0 M NH₃/CH₃OH elution) to affordpyrrolidine 1f as a yellow solid (381 mg), containing residual solvent.¹H NMR (DMSO-d₆, δ=2.5 ppm, 400 MHz): 11.93 (br s, 1H), 9.85 (s, 1H),8.82 (s, 1H), 8.49 (s, 1H), 8.19 (d, J=8.6, 1H), 7.89 (m, 4H), 7.81 (d,J=8.8, 1H), 7.66 (d, J=8.8, 2H), 7.56 (app br s, 1H), 7.00 (d, J=8.8,2H), 4.89 (m, 0.04H), 4.20 (m, 0.96H), 3.76 (m, 4H), 3.12 (m, 4H),3.02-2.96 (m, 1H), 2.91-2.85 (m, 1H), 2.12-2.04 (m, 1H), 1.95-1.87 (m,1H), 1.84-1.70 (m, 2H). LC (Cond. I): RT=1.12 min; >95% homogeneityindex. LC/MS: Anal. Calcd. for [M+H]⁺ C₃₁H₃₂N₇O: 518.27; found 518.19.

Example 1

HATU (30.9 mg, 0.081 mmol) was added in one batch to a DMF (1.5 mL)solution of pyrrolidine 1f (39.9 mg, 0.077 mmol),(S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (17.1 mg, 0.098 mmol)and diisopropylethylamine (30 μL, 0.17 mmol), and the reaction mixturewas stirred at ambient condition for 160 minutes. The volatile componentwas removed in vacuo and the residue was first passed through MCX column(CH₃OH wash; 2.0 M NH₃/CH₃ OH elution), concentrated and then purifiedwith a reverse phase HPLC (CH₃OH/H₂O/TFA) to afford the TFA salt ofExample 1 as orangish-red foam (49.3 mg). ¹H NMR (DMSO-d₆, δ=2.5 ppm,400 MHz): 11.40 (br s, 1H), 9.07 (s, 1H), 8.88 (s, 1H), 8.51 (dd, J=8.9,1.8, 1H), 8.17 (s, 1H), 8.09 (d, J=8.6, 2H), 7.99 (d, J=8.3, 2H), 7.94(d, J=8.5, 11H), 7.59 (d, J=9.0, 2H), 7.34 (d, J=8.5, ˜1H), 7.08 (d,J=9.1, 2H), 5.59 (m, 0.07H), 5.16 (m, 0.93H), 4.12 (m, ˜1H), 3.91-3.81(m, ˜2H), 3.77 (m, 4H), 3.55 (s, 2.80H), 3.34 (s, 0.20H), 3.18 (m, 4H),2.44-2.37 (m, 1H), 2.20-2.00 (m, 4H), 0.91-0.79 (m, 6H). LC (Cond. I):RT=1.26 min; >95% homogeneity index. LC/MS: Anal. Calcd. for [M+H]⁺C₃₈H₄₃N₈O₄: 675.34; found 675.24.

Examples 2-5

Examples 2-5 were prepared as TFA salts by employing the proceduredescribed for Example 1 and appropriate acids. In the case of Examples4-5, an additional purification was conducted with a reverse phase HPLCsystem utilizing CH₃CN/H₂O/TFA.

Example

RT (LC-Cond.); % homogeneity index; MS data 2

1.31 min (Cond. I); >95%; LC/MS: Anal. Calcd. for [M + H]⁺ C₃₈H₄₃N₈O₄:675.24; found 675.24 3

1.23 min (Cond. I); >95%; LC/MS: Anal. Calcd. for [M + H]⁺ C₄₃H₄₇N₈O₂:707.38; found 707.23. 4

1.23 min (Cond. I); >95%; LC/MS: Anal. Calcd. for [M + H]⁺ C₃₆H₃₉N₈O₄:647.31; found 647.19 5

1.35 min (Cond. I); >95%; LC/MS: Anal. Calcd. for [M + H]⁺ C₄₁H₄₁N₈O₄:709.33; found 709.16

Example 6

Acetic anhydride (40 μL, 0.42 mmol) was added to a heterogeneous mixtureof pyrrolidine 1f (49 mg, 0.095 mmol) and Et₃N (30 μL, 0.22 mmol) inCH₂Cl₂ (1.5 mL), and stirred at ambient condition for 90 minutes. Thevolatile component was removed in vacuo, and NH₃/CH₃OH (2.0 M, 3 mL) wasadded to the residue and the mixture was stirred for 105 minutes. Theresultant precipitate was filtered and washed with CH₃OH (1.5 mL), andthen was exposed to high vacuum to afford Example 6 as a dull-yellowsolid (31.1 mg), solvated with ˜0.5 mol equiv of CH₃OH. LC (Cond. I):RT=1.26 min; >95% homogeneity index. LC/MS: Anal. Calcd. for [M+H]⁺C₃₃H₃₄N₇O₂: 560.28; found 560.20.

Biological Activity

An HCV Replion assay was utilized in the present disclosure, and wasprepared, conducted and validated as described in commonly ownedPCT/US2006/022197 and in O'Boyle et. al. Antimicrot Agents Chemother.2005 April; 49(4):1346-53.

HCV-neo replicon cells were used to test the currently describedcompound series as well as cells resistant to compound A containingmutations in NS5A (described in application PCT/US2006/022197). Thecompounds tested were determined to have more than 10-fold lessinhibitory activity on cells containing the mutation than wild-typecells indicating a related mechanism of action between the two compoundseries. Thus, the compounds of the present disclosure can be effectiveto inhibit the function of the HCV NS5A protein and are understood to beas effective in combinations as previously described in applicationPCT/US2006/022197 and commonly owned WO 04/014852. Further, thecompounds of the present disclosure can be effective against the HCV 1bgenotype. It should also be understood that the compounds of the presentdisclosure can inhibit multiple genotypes of HCV. Table 2 shows the EC50values of representative compounds of the present disclosure against theHCV 1b genotype. In one embodiment compounds of the present disclosureare active against the 1a, 1b, 2a, 2b, 3a, 4a, and 5a genotypes.Activity ranges are as follows: A=501 nM-1 μM; B 1-500 nM; C=100-999 pM.

The compounds of the present disclosure may inhibit HCV by mechanisms inaddition to or other than NS5A inhibition. In one embodiment thecompounds of the present disclosure inhibit HCV replicon and in anotherembodiment the compounds of the present disclosure inhibit NS5A.

TABLE 2 Example Number Range/Value Example 1 step e B Example 1 step f1.51 μM Example 1 B Example 2 270 nM Example 3 46 pM Example 4 B Example5 C Example 6 A

It will be evident to one skilled in the art that the present disclosureis not limited to the foregoing illustrative examples, and that it canbe embodied in other specific forms without departing from the essentialattributes thereof. It is therefore desired that the examples beconsidered in all respects as illustrative and not restrictive,reference being made to the appended claims, rather than to theforegoing examples, and all changes which come within the meaning andrange of equivalency of the claims are therefore intended to be embracedtherein.

The compounds of the present disclosure may inhibit HCV by mechanisms inaddition to or other than NS5A inhibition. In one embodiment thecompounds of the present disclosure inhibit HCV replicon and in anotherembodiment the compounds of the present disclosure inhibit NS5A.Compounds of the present disclosure may inhibit multiple genotypes ofHCV.

1. A compound of Formula (I)

or a pharmaceutically acceptable salt thereof, wherein a, b, and d areeach selected from CH and N; provided at least one of a, b, and d is N;n is 1; u is 0, 1, 2, or 3; A is selected from phenyl and a six-memberedheteroaromatic ring containing one, two, or three nitrogen atoms; B is afive-membered aromatic ring containing one, two, or three heteroatomsindependently selected from nitrogen, oxygen, and sulfur; R¹ is selectedfrom hydrogen, alkyl, and haloalkyl; R² is morpholinyl; each R³ isindependently selected from alkoxy, alkoxyalkyl, alkoxycarbonyl, alkyl,arylalkoxycarbonyl, carboxy, formyl, halo, haloalkyl, hydroxy,hydroxyalkyl, —NR^(a)R^(b), (NR^(a)R^(b))alkyl, and(NR^(a)R^(b))carbonyl; R⁴ is selected from hydrogen, alkoxyalkyl,alkoxycarbonyl, alkoxycarbonylalkyl, alkyl, arylalkoxycarbonyl, carboxy,haloalkyl, heterocyclylalkyl, hydroxyalkyl, (NR^(a)R^(b))carbonyl, andtrialkylsilylalkoxyalkyl; R⁵ is selected from

m is 0, 1, or 2; o is 1, 2, or 3; s is independently 0, 1, 2, 3, or 4; Xis independently selected from O, S, S(O), SO₂, CH₂, CHR⁶, and C(R⁶)₂;provided that when m is 0, X is selected from CH₂, CHR⁶, and C(R⁶)₂;each R⁶ is independently selected from alkoxy, alkyl, aryl, halo,haloalkyl, hydroxy, and —NR^(a)R^(b), wherein the alkyl can optionallyform a fused three- to six-membered ring with an adjacent carbon atom,wherein the three- to six-membered ring is optionally substituted withone or two alkyl groups; each R⁷ is independently selected from hydrogenand R¹¹—C(O)—, and R¹¹—C(S)—; R⁸ is selected from hydrogen and alkyl; R⁹and R¹⁰ are each independently selected from hydrogen, alkenyl,alkoxyalkyl, alkyl, haloalkyl, and (NR^(a)R^(b))alkyl; or, R⁹ and R¹⁰,together with the carbon atom to which they are attached, form a five orsix membered saturated ring optionally containing one or two heteroatomsselected from NR^(z), O, and S; wherein R^(z) is selected from hydrogenand alkyl; each R¹¹ is independently selected from alkoxy, alkoxyalkyl,alkoxycarbonyl, alkoxycarbonylalkyl, alkyl, alkylcarbonylalkyl, aryl,arylalkenyl, arylalkoxy, arylalkyl, aryloxyalkyl, cycloalkyl,(cycloalkyl)alkenyl, (cycloalkyl)alkyl, cycloalkyloxyalkyl, haloalkyl,heterocyclyl, heterocyclylalkenyl, heterocyclylalkoxy,heterocyclylalkyl, heterocyclyloxyalkyl, hydroxyalkyl, —NR^(c)R^(d),(NR^(c)R^(d))alkenyl, (NR^(c)R^(d))alkyl, and (NR^(c)R^(d))carbonyl;R^(a) and R^(b) are independently selected from hydrogen, alkenyl, andalkyl; R^(c) and R^(d) are independently selected from hydrogen,alkenyloxycarbonyl, alkoxyalkylcarbonyl, alkoxycarbonyl, alkyl,alkylcarbonyl, alkylsulfonyl, aryl, arylalkoxycarbonyl, arylalkyl,arylalkylcarbonyl, arylcarbonyl, aryloxycarbonyl arylsulfonyl,cycloalkyl, cycloalkylsulfonyl, formyl, haloalkoxycarbonyl,heterocyclyl, heterocyclylalkoxycarbonyl, heterocyclylalkyl,heterocyclylalkylcarbonyl, heterocyclylcarbonyl,heterocyclyloxycarbonyl, hydroxyalkylcarbonyl, (NR^(e)R^(f))alkyl,(NR^(e)R^(f))alkylcarbonyl, (NR^(e)R^(f))carbonyl,(NR^(e)R^(f))sulfonyl, —C(NCN)OR′, and —C(NCN)NR^(x)R^(y), wherein R′ isselected from alkyl and unsubstituted phenyl, and wherein the alkyl partof the arylalkyl, the arylalkylcarbonyl, the heterocyclylalkyl, and theheterocyclylalkylcarbonyl are further optionally substituted with one—NR^(e)R^(f) group; and wherein the aryl, the aryl part of thearylalkoxycarbonyl, the arylalkyl, the arylalkylcarbonyl, thearylcarbonyl, the aryloxycarbonyl, and the arylsulfonyl, theheterocyclyl, and the heterocyclyl part of theheterocyclylalkoxycarbonyl, the heterocyclylalkyl, theheterocyclylalkylcarbonyl, the heterocyclylcarbonyl, and theheterocyclyloxycarbonyl are further optionally substituted with one,two, or three substituents independently selected from alkoxy, alkyl,cyano, halo, haloalkoxy, haloalkyl, and nitro; R^(e) and R^(f) areindependently selected from hydrogen, alkyl, unsubstituted aryl,unsubstituted arylalkyl, unsubstituted cycloalkyl, unsubstituted(cyclolalkyl)alkyl, unsubstituted heterocyclyl, unsubstitutedheterocyclylalkyl, (NR^(x)R^(y))alkyl, and (NR^(x)R^(y))carbonyl; andR^(x) and R^(y) are independently selected from hydrogen,alkoxycarbonyl, alkyl, alkylcarbonyl, unsubstituted aryl, unsubstitutedarylalkoxycarbonyl, unsubstituted arylalkyl, unsubstituted cycloalkyl,unsubstituted heterocyclyl, and (NR^(x′)R^(y′))carbonyl, wherein R^(x′)and R^(y′) are independently selected from hydrogen and alkyl.
 2. Acompound of claim 1, or a pharmaceutically acceptable salt thereof,wherein R⁵ is


3. A compound of claim 2, or a pharmaceutically acceptable salt thereof,wherein m is
 1. 4. A compound of claim 2, or a pharmaceuticallyacceptable salt thereof, wherein X is CH₂.
 5. A compound of claim 2, ora pharmaceutically acceptable salt thereof, wherein s is
 0. 6. Acompound of claim 2, or a pharmaceutically acceptable salt thereof,wherein R⁷ is selected from hydrogen and R¹¹—C(O)—.
 7. A compound ofclaim 6 wherein R¹¹ is independently selected from arylalkyl,(cycloalkyl)alkyl, and (NR^(c)R^(d))alkyl.
 8. A compound of claim 1, ora pharmaceutically acceptable salt thereof, wherein u is
 0. 9. Acompound of claim 1, or a pharmaceutically acceptable salt thereof,wherein R⁴ is hydrogen.
 10. A compound of claim 1, or a pharmaceuticallyacceptable salt thereof, wherein R¹ is hydrogen.
 11. A compound of claim1, or a pharmaceutically acceptable salt thereof, wherein n is 2; andone R² is hydrogen and the other is selected from heterocyclyl and—NR^(c)R^(d).
 12. A compound of Formula (II)

or a pharmaceutically acceptable salt thereof, wherein R⁷ is selectedfrom hydrogen and R¹¹—C(O)—; and R¹¹ is independently selected fromalkoxy, alkoxyalkyl, alkoxycarbonyl, alkoxycarbonylalkyl, alkyl,alkylcarbonylalkyl, aryl, arylalkenyl, arylalkoxy, arylalkyl,aryloxyalkyl, cycloalkyl, (cycloalkyl)alkenyl, (cycloalkyl)alkyl,cycloalkyloxyalkyl, haloalkyl, heterocyclyl, heterocyclylalkenyl,heterocyclylalkoxy, heterocyclylalkyl, heterocyclyloxyalkyl,hydroxyalkyl, —NR^(c)R^(d), (NR^(c)R^(d))alkenyl, (NR^(c)R^(d))alkyl,and (NR^(c)R^(d))carbonyl; R^(a) and R^(b) are independently selectedfrom hydrogen, alkenyl, and alkyl; R^(c) and R^(d) are independentlyselected from hydrogen, alkenyloxycarbonyl, alkoxyalkylcarbonyl,alkoxycarbonyl, alkyl, alkylcarbonyl, alkylsulfonyl, aryl,arylalkoxycarbonyl, arylalkyl, arylalkylcarbonyl, arylcarbonyl,aryloxycarbonyl, arylsulfonyl, cycloalkyl, cycloalkylsulfonyl, formyl,haloalkoxycarbonyl, heterocyclyl, heterocyclylalkoxycarbonyl,heterocyclylalkyl, heterocyclylalkylcarbonyl, heterocyclylcarbonyl,heterocyclyloxycarbonyl, hydroxyalkylcarbonyl, (NR^(e)R^(f))alkyl,(NR^(e)R^(f))alkylcarbonyl, (NR^(e)R^(f))carbonyl,(NR^(e)R^(f))sulfonyl, —C(NCN)OR′, and —C(NCN)NR^(x)R^(y), wherein R′ isselected from alkyl and unsubstituted phenyl, and wherein the alkyl partof the arylalkyl, the arylalkylcarbonyl, the heterocyclylalkyl, and theheterocyclylalkylcarbonyl are further optionally substituted with one—NR^(e)R^(f) group; and wherein the aryl, the aryl part of thearylalkoxycarbonyl, the arylalkyl, the arylalkylcarbonyl, thearylcarbonyl, the aryloxycarbonyl, and the arylsulfonyl, theheterocyclyl, and the heterocyclyl part of theheterocyclylalkoxycarbonyl, the heterocyclylalkyl, theheterocyclylalkylcarbonyl, the heterocyclylcarbonyl, and theheterocyclyloxycarbonyl are further optionally substituted with one,two, or three substituents independently selected from alkoxy, alkyl,cyano, halo, haloalkoxy, haloalkyl, and nitro; R^(e) and R^(f) areindependently selected from hydrogen, alkyl, unsubstituted aryl,unsubstituted arylalkyl, unsubstituted cycloalkyl, unsubstituted(cyclolalkyl)alkyl, unsubstituted heterocyclyl, unsubstitutedheterocyclylalkyl, (NR^(x)R^(y))alkyl, and (NR^(x)R^(y))carbonyl; andR^(x) and R^(y) are independently selected from hydrogen,alkoxycarbonyl, alkyl, alkylcarbonyl, unsubstituted aryl, unsubstitutedarylalkoxycarbonyl, unsubstituted arylalkyl, unsubstituted cycloalkyl,unsubstituted heterocyclyl, and (NR^(x′)R^(y′))carbonyl, wherein R^(x′)and R^(y′) are independently selected from hydrogen and alkyl.
 13. Acompound of claim 12, or a pharmaceutically acceptable salt thereof,wherein R¹¹ is selected from alkoxy, alkyl, arylalkyl, and(NR^(c)R^(d))alkyl.
 14. A compound selected from:

or a pharmaceutically acceptable salt thereof.
 15. A compositioncomprising a compound of claim 1, or a pharmaceutically acceptable saltthereof, and a pharmaceutically acceptable carrier.
 16. The compositionof claim 15 further comprising one or two additional compounds havinganti-HCV activity.
 17. The composition of claim 16 wherein at least oneof the additional compounds is an interferon or a ribavirin.
 18. Thecomposition of claim 17 wherein the interferon is selected frominterferon alpha 2B, pegylated interferon alpha, consensus interferon,interferon alpha 2A, and lymphoblastiod interferon tau.
 19. Thecomposition of claim 16 wherein at least one of the additional compoundsis selected from interleukin 2, interleukin 6, interleukin 12, acompound that enhances the development of a type 1 helper T cellresponse, interfering RNA, anti-sense RNA, Imiqimod, ribavirin, aninosine 5′-monophospate dehydrogenase inhibitor, amantadine, andrimantadine.
 20. The composition of claim 16 wherein at least one of theadditional compounds is effective to inhibit the function of a targetselected from HCV metalloprotease, HCV serine protease, HCV polymerase,HCV helicase, HCV NS4B protein, HCV entry, HCV assembly, HCV egress, HCVNS5A protein, and IMPDH for the treatment of an HCV infection.
 21. Amethod of treating an HCV infection in a patient, comprisingadministering to the patient a therapeutically effective amount of acompound of claim 1, or a pharmaceutically acceptable salt thereof. 22.The method of claim 21 further comprising administering one or twoadditional compounds having anti-HCV activity prior to, after orsimultaneously with the compound of claim 1, or a pharmaceuticallyacceptable salt thereof.
 23. The method of claim 22 wherein at least oneof the additional compounds is an interferon or a ribavirin.
 24. Themethod of claim 23 wherein the interferon is selected from interferonalpha 2B, pegylated interferon alpha, consensus interferon, interferonalpha 2A, and lymphoblastiod interferon tau.
 25. The method of claim 22wherein at least one of the additional compounds is selected frominterleukin 2, interleukin 6, interleukin 12, a compound that enhancesthe development of a type 1 helper T cell response, interfering RNA,anti-sense RNA, Imiqimod, ribavirin, an inosine 5′-monophospatedehydrogenase inhibitor, amantadine, and rimantadine.
 26. The method ofclaim 22 wherein at least one of the additional compounds is effectiveto inhibit the function of a target selected from HCV metalloprotease,HCV serine protease, HCV polymerase, HCV helicase, HCV NS4B portein, HCVentry, HCV assembly, HCV egress, HCV NS5A protein, and IMPDH for thetreatment of an HCV infection.